Substituted nucleosides, nucleotides and analogs thereof

ABSTRACT

Disclosed herein are nucleosides, nucleotides and nucleotide analogs, methods of synthesizing the same and methods of treating diseases and/or conditions such as a Coronaviridae virus, a Togaviridae virus, a Hepeviridae virus and/or a Bunyaviridae virus infection with one or more nucleosides, nucleotides and nucleotide analogs.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified, for example, in the Application Data Sheet or Request asfiled with the present application, are hereby incorporated by referenceunder 37 CFR 1.57, and Rules 4.18 and 20.6.

BACKGROUND

Field

The present application relates to the fields of chemistry, biochemistryand medicine. More particularly, disclosed herein are nucleosides,nucleotides and nucleotide analogs, pharmaceutical compositions thatinclude one or more nucleosides, nucleotides and/or nucleotide analogsand methods of synthesizing the same. Also disclosed herein are methodsof treating diseases and/or conditions with a nucleoside, a nucleotideand/or a nucleotide analog, alone or in combination therapy with one ormore other agents.

Description

Nucleoside analogs are a class of compounds that have been shown toexert antiviral and anticancer activity both in vitro and in vivo, andthus, have been the subject of widespread research for the treatment ofviral infections. Nucleoside analogs are usually therapeuticallyinactive compounds that are converted by host or viral enzymes to theirrespective active anti-metabolites, which, in turn, may inhibitpolymerases involved in viral or cell proliferation. The activationoccurs by a variety of mechanisms, such as the addition of one or morephosphate groups and, or in combination with, other metabolic processes.

SUMMARY

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Coronaviridae virus infection that can includeadministering to a subject identified as suffering from theCoronaviridae virus infection an effective amount of one or morecompounds of Formula (I), or a pharmaceutically acceptable salt ofthereof, or a pharmaceutical composition that includes one or morecompounds of Formula (I), or a pharmaceutically acceptable salt thereof.Other embodiments described herein relate to using one or more compoundsof Formula (I), or a pharmaceutically acceptable salt thereof, in themanufacture of a medicament for ameliorating and/or treating aCoronaviridae virus infection. Still other embodiments described hereinrelate to one or more compounds of Formula (I), or a pharmaceuticallyacceptable salt thereof, or a pharmaceutical composition that includesone or more compounds of Formula (I), or a pharmaceutically acceptablesalt thereof, that can be used for ameliorating and/or treating aCoronaviridae virus infection.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Coronaviridae virus infection that can includecontacting a cell infected with the Coronaviridae virus with aneffective amount of one or more compounds described herein (for example,a compound of Formula (I), or a pharmaceutically acceptable saltthereof), or a pharmaceutical composition that includes one or morecompounds described herein, or a pharmaceutically acceptable saltthereof. Other embodiments described herein relate to using one or morecompounds described herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof) in the manufacture of amedicament for ameliorating and/or treating a Coronaviridae virusinfection that can include contacting a cell infected with theCoronaviridae virus with an effective amount of said compound(s). Stillother embodiments described herein relate to one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein, or apharmaceutically acceptable salt thereof, that can be used forameliorating and/or treating a Coronaviridae virus infection bycontacting a cell infected with the Coronaviridae virus with aneffective amount of said compound(s).

Some embodiments disclosed herein relate to a method of inhibitingreplication of a Coronaviridae virus that can include contacting a cellinfected with the Coronaviridae virus with an effective amount of one ormore compounds described herein (for example, a compound of Formula (I),or a pharmaceutically acceptable salt of the foregoing), or apharmaceutical composition that includes one or more compounds describedherein, or a pharmaceutically acceptable salt thereof. Other embodimentsdescribed herein relate to using one or more compounds described herein(for example, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof) in the manufacture of a medicament forinhibiting replication of a Coronaviridae virus that can includecontacting a cell infected with the Coronaviridae virus with aneffective amount of said compound(s). Still other embodiments describedherein relate to one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt of theforegoing), or a pharmaceutical composition that includes one or morecompounds described herein, or a pharmaceutically acceptable saltthereof, that can be used for inhibiting replication of a Coronaviridaevirus by contacting a cell infected with the Coronaviridae virus with aneffective amount of said compound(s). In some embodiments, theCoronaviridae virus can be MERS-CoV and/or SARS-CoV.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Togaviridae virus infection that can includeadministering to a subject identified as suffering from the Togaviridaevirus infection an effective amount of one or more compounds of Formula(I), or a pharmaceutically acceptable salt of thereof, or apharmaceutical composition that includes one or more compounds ofFormula (I), or a pharmaceutically acceptable salt thereof. Otherembodiments described herein relate to using one or more compounds ofFormula (I), or a pharmaceutically acceptable salt thereof, in themanufacture of a medicament for ameliorating and/or treating aTogaviridae virus infection. Still other embodiments described hereinrelate to one or more compounds of Formula (I), or a pharmaceuticallyacceptable salt thereof, or a pharmaceutical composition that includesone or more compounds of Formula (I), or a pharmaceutically acceptablesalt thereof, that can be used for ameliorating and/or treating aTogaviridae virus infection.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Togaviridae virus infection that can includecontacting a cell infected with the Togaviridae virus with an effectiveamount of one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt thereof),or a pharmaceutical composition that includes one or more compoundsdescribed herein, or a pharmaceutically acceptable salt thereof. Otherembodiments described herein relate to using one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof) in the manufacture of amedicament for ameliorating and/or treating a Togaviridae virusinfection that can include contacting a cell infected with theTogaviridae virus with an effective amount of said compound(s). Stillother embodiments described herein relate to one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein, or apharmaceutically acceptable salt thereof, that can be used forameliorating and/or treating a Togaviridae virus infection by contactinga cell infected with the Togaviridae virus with an effective amount ofsaid compound(s).

Some embodiments disclosed herein relate to a method of inhibitingreplication of a Togaviridae virus that can include contacting a cellinfected with the Togaviridae virus with an effective amount of one ormore compounds described herein (for example, a compound of Formula (I),or a pharmaceutically acceptable salt of the foregoing), or apharmaceutical composition that includes one or more compounds describedherein, or a pharmaceutically acceptable salt thereof. Other embodimentsdescribed herein relate to using one or more compounds described herein(for example, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof) in the manufacture of a medicament forinhibiting replication of a Togaviridae virus that can includecontacting a cell infected with the Togaviridae virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt of theforegoing), or a pharmaceutical composition that includes one or morecompounds described herein, or a pharmaceutically acceptable saltthereof, that can be used for inhibiting replication of a Togaviridaevirus by contacting a cell infected with the Togaviridae virus with aneffective amount of said compound(s). In some embodiments, theTogaviridae virus can be a VEE virus, Chikungunya virus and/or analphavirus.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Hepeviridae virus infection that can includeadministering to a subject identified as suffering from the Hepeviridaevirus infection an effective amount of one or more compounds of Formula(I), or a pharmaceutically acceptable salt of thereof, or apharmaceutical composition that includes one or more compounds ofFormula (I), or a pharmaceutically acceptable salt thereof. Otherembodiments described herein relate to using one or more compounds ofFormula (I), or a pharmaceutically acceptable salt thereof, in themanufacture of a medicament for ameliorating and/or treating aHepeviridae virus infection. Still other embodiments described hereinrelate to one or more compounds of Formula (I), or a pharmaceuticallyacceptable salt thereof, or a pharmaceutical composition that includesone or more compounds of Formula (I), or a pharmaceutically acceptablesalt thereof, that can be used for ameliorating and/or treating aHepeviridae virus infection.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Hepeviridae virus infection that can includecontacting a cell infected with the Hepeviridae virus with an effectiveamount of one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt thereof),or a pharmaceutical composition that includes one or more compoundsdescribed herein, or a pharmaceutically acceptable salt thereof. Otherembodiments described herein relate to using one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof) in the manufacture of amedicament for ameliorating and/or treating a Hepeviridae virusinfection that can include contacting a cell infected with theHepeviridae virus with an effective amount of said compound(s). Stillother embodiments described herein relate to one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein, or apharmaceutically acceptable salt thereof, that can be used forameliorating and/or treating a Hepeviridae virus infection by contactinga cell infected with the Hepeviridae virus with an effective amount ofsaid compound(s).

Some embodiments disclosed herein relate to a method of inhibitingreplication of a Hepeviridae virus that can include contacting a cellinfected with the Hepeviridae virus with an effective amount of one ormore compounds described herein (for example, a compound of Formula (I),or a pharmaceutically acceptable salt of the foregoing), or apharmaceutical composition that includes one or more compounds describedherein, or a pharmaceutically acceptable salt thereof. Other embodimentsdescribed herein relate to using one or more compounds described herein(for example, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof) in the manufacture of a medicament forinhibiting replication of a Hepeviridae virus that can includecontacting a cell infected with the Hepeviridae virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt of theforegoing), or a pharmaceutical composition that includes one or morecompounds described herein, or a pharmaceutically acceptable saltthereof, that can be used for inhibiting replication of a Hepeviridaevirus by contacting a cell infected with the Hepeviridae virus with aneffective amount of said compound(s). In some embodiments, theHepeviridae virus can be Hepatitis E virus.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Bunyaviridae virus infection that can includeadministering to a subject identified as suffering from the Bunyaviridaevirus infection an effective amount of one or more compounds of Formula(I), or a pharmaceutically acceptable salt of thereof, or apharmaceutical composition that includes one or more compounds ofFormula (I), or a pharmaceutically acceptable salt thereof. Otherembodiments described herein relate to using one or more compounds ofFormula (I), or a pharmaceutically acceptable salt thereof, in themanufacture of a medicament for ameliorating and/or treating aBunyaviridae virus infection. Still other embodiments described hereinrelate to one or more compounds of Formula (I), or a pharmaceuticallyacceptable salt thereof, or a pharmaceutical composition that includesone or more compounds of Formula (I), or a pharmaceutically acceptablesalt thereof, that can be used for ameliorating and/or treating aBunyaviridae virus infection.

Some embodiments disclosed herein relate to a method of amelioratingand/or treating a Bunyaviridae virus infection that can includecontacting a cell infected with the Bunyaviridae virus with an effectiveamount of one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt thereof),or a pharmaceutical composition that includes one or more compoundsdescribed herein, or a pharmaceutically acceptable salt thereof. Otherembodiments described herein relate to using one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof) in the manufacture of amedicament for ameliorating and/or treating a Bunyaviridae virusinfection that can include contacting a cell infected with theBunyaviridae virus with an effective amount of said compound(s). Stillother embodiments described herein relate to one or more compoundsdescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein, or apharmaceutically acceptable salt thereof, that can be used forameliorating and/or treating a Bunyaviridae virus infection bycontacting a cell infected with the Bunyaviridae virus with an effectiveamount of said compound(s).

Some embodiments disclosed herein relate to a method of inhibitingreplication of a Bunyaviridae virus that can include contacting a cellinfected with the Bunyaviridae virus with an effective amount of one ormore compounds described herein (for example, a compound of Formula (I),or a pharmaceutically acceptable salt of the foregoing), or apharmaceutical composition that includes one or more compounds describedherein, or a pharmaceutically acceptable salt thereof. Other embodimentsdescribed herein relate to using one or more compounds described herein(for example, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof) in the manufacture of a medicament forinhibiting replication of a Bunyaviridae virus that can includecontacting a cell infected with the Bunyaviridae virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to one or more compounds described herein (for example, acompound of Formula (I), or a pharmaceutically acceptable salt of theforegoing), or a pharmaceutical composition that includes one or morecompounds described herein, or a pharmaceutically acceptable saltthereof, that can be used for inhibiting replication of a Bunyaviridaevirus by contacting a cell infected with the Bunyaviridae virus with aneffective amount of said compound(s). In some embodiments, theBunyaviridae virus can be a Rift Valley Fever virus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the structure of K22.

DETAILED DESCRIPTION

Coronaviridae viruses are a family of enveloped, positive-stranded,single-stranded, spherical RNA viruses. Coronaviruses are named for thecrown-like spikes on their surface. The Coronaviridae family includestwo sub-families, Coronavirus and Torovirus. The Coronavirus genus has ahelical nucleocapsid, and Torovirus genus has a tubular nucleocapsid.Within the Coronavirus sub-family are the following genera:Alphacoronavirus, Betacoronavirus, Gammacoronavirus andDeltacoronavirus. Genera within the Torovirus sub-family are Bafinivirusand Torovirus.

Middle East respiratory syndrome coronavirus (MERS-CoV) is a member ofthe Betacoronavirus genus, and causes Middle East Respiratory Syndrome(MERS). MERS is an acute respiratory illness. About half of theindividuals confirmed to have been infected with MERS died. There is nocurrent treatment or vaccine for MERS.

Another member of the Betacornavirus genus is SARS coronavirus(SARS-CoV). SARS-Co-V is the virus that causes severe acute respiratorysyndrome (SARS). SARS was first reported in Asia in February 2003. SARSis an airborne virus, and can spread by the inhalation of small dropletsof water that an infected individuals releases into the air (forexample, by coughing and/or sneezing), touching a contaminated surfaceand/or by being in close proximity of an infected individual (forexample, cared for or lived with a person known to have SARS or having ahigh likelihood of direct contact with respiratory secretions and/orbody fluids of a patient known to have SARS, including kissing orembracing, sharing eating or drinking utensils, close conversation(within 3 feet), physical examination, and any other direct physicalcontact between people).

The two genera with the Togaviridae family are Alphavirus and Rubivirus.Viruses within this family are enveloped, positive-sense,single-stranded, linear RNA viruses. To date, Rubivirus has one species,Rubella virus. Viruses classified in the Alphavirus genus includeVenezuelan equine encephalitis (VEE) viruses. VEE viruses are mainlytransmitted by mosquitos, and causes Venezuelan equine encephalitis andencephalomyelitis. The VEE complex of viruses includes six antigenicsubtypes (I-VI) divided by antigenic variants. Additionally, VEE virusesare divided into two groups, epizootic (or epidemic) and enzootic (orendemic). Within subtype I, the Venezuelan equine encephalomyelitisvirus (VEEV), is divided into five antigenic variants (variants AB-F).Subtype II is known as Everglades virus, subtype III as Mucambo virus,and subtype IV as Pixuna virus. Equine species along with humans can beinfected with VEE viruses. Currently, there is not vaccine available forhorses or humans.

Another member of the Alphavirus genus is Chikungunya (CHIKV).Chikungunya is an arthropod-borne virus and can be transmitted to humansby mosquitoes (such as Aedes mosquitos). Currently, there are nospecific treatments for Chikungunya, and no vaccine is currentlyavailable.

Other Alphaviruses are Barmah Forest virus, Mayaro virus (MAYV),O'nyong'nyong virus, Ross River virus (RRV), Semliki Forest virus,Sindbis virus (SINV), Una virus, Eastern equine encephalitis virus (EEE)and Western equine encephalomyelitis (WEE). These Alphaviruses aremainly arthropod-borne, and transmitted via mosquitos.

The Hepeviridae family includes non-enveloped, positive-sense,single-stranded, spherical RNA viruses and includes the Hepevirus genus.A member of the hepevirus genus is the Hepatitis E virus (HEV).Hepatitis E has 4 genotypes. Genotype 1 has been classified into fivesubtypes. Genotype 2 has been classified into two subtypes. Genotype 3has been classified into 10 subtypes, and genotypes 4 have been intoseven subtypes. Hepatitis E virus is transmitted namely through thefecal-oral route (for example, by drinking water contaminated withfeces) but can also be foodborne, transmitted via transfusion and/orvertically transmitted. Fulminant hepatitis (acute liver failure) can becaused by a Hepatitis E virus infection. Chronic and reactivation of ahepatitis E infection has been reported in immunosuppressed individuals.Also, liver fibrosis and liver cirrhosis can result from a Hepatitis Einfection. There is currently no FDA-approved vaccine for Hepatitis E.

The Bunyaviridae family has over 300 members which are grouped into fivegenera: Bunyavirus, Hantavirus, Nairovirus, Phlebovirus and Tospovirus.The Bunyaviridae family is a family of enveloped, negative-stranded,single-stranded, spherical RNA viruses.

Rift Valley Fever virus is a member of the Phlebovirus genus. Humans canbe infected from direct or indirect contact with the blood or organs ofinfected animals and/or infected inserts (for example, flies andmosquitoes). Severe forms of Rift Valley Fever virus are ocular form,meningoencephalitis form and hemorrhagic fever form. Although aninactive vaccine has been developed for human use, the vaccine is notlicensed or commercially available. Animal vaccines are available;however, the uses of these vaccines are limited because of deleteriouseffects and/or incomplete protection. The current treatment for a RiftValley Fever virus infection is supportive.

Thrombocytopenia syndrome virus is another member of the Phlebovirusgenus. In humans, thrombocytopenia syndrome virus causes severe feverwith thrombocytopenia syndrome (SFTS). SFTS has been reported in severalprovidences of China and has been confirmed in the western regions ofJapan.

Crimean-Congo hemorrhagic fever virus (CCHF) is a member of theNairovirus genus, and causes severe viral hemorrhagic fever outbreaks.CCHF is primarily transmitted to people from ticks and livestockanimals, and human-to-human transmission can occur through close contactwith the blood, secretions, organs or other bodily fluids of an infectedperson. California encephalitis virus causes encephalitis in humans, andis an arthropod-borne virus. Although most subjects recover,approximately 20% develop behavioral problems and/or have recurrentseizures.

Hantaviruses are the cause of hantavirus hemorrhagic fever with renalsyndrome (HFRS) (also known as Korean hemorrhagic fever, epidemichemorrhagic fever, and nephropathis epidemica) and hantavirus pulmonarysyndrome (HPS), which are potentially fatal diseases in humans.Hantaviruses are carried by rodents and infection can occur throughdirect contact with feces, saliva or urine of the infected rodentsand/or by inhalation of the virus in rodent excreta. Treatment of HFRSand HPS is supportive as currently there is not specific cure orvaccine.

DEFINITIONS

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as is commonly understood by one of ordinary skillin the art. All patents, applications, published applications and otherpublications referenced herein are incorporated by reference in theirentirety unless stated otherwise. In the event that there are aplurality of definitions for a term herein, those in this sectionprevail unless stated otherwise.

As used herein, any “R” group(s) such as, without limitation, R¹, R²,R³, R⁴, R^(5A), R^(5B), R^(6A), R^(6B), R^(6C), R^(6D), R^(6E), R^(6F),R^(6G), R^(6H), R^(7A), R^(7B), R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵,R¹⁶, R¹⁷, R¹⁸, R^(A1), R^(A2), R^(A3) and R^(A4) represent substituentsthat can be attached to the indicated atom. An R group may besubstituted or unsubstituted. If two “R” groups are described as being“taken together” the R groups and the atoms they are attached to canform a cycloalkyl, cycloalkenyl, aryl, heteroaryl or heterocycle. Forexample, without limitation, if R^(a) and R^(b) of an NR^(a)R^(b) groupare indicated to be “taken together,” it means that they are covalentlybonded to one another to form a ring:

In addition, if two “R” groups are described as being “taken together”with the atom(s) to which they are attached to form a ring as analternative, the R groups are not limited to the variables orsubstituents defined previously.

Whenever a group is described as being “optionally substituted” thatgroup may be unsubstituted or substituted with one or more of theindicated substituents. Likewise, when a group is described as being“unsubstituted or substituted” if substituted, the substituent(s) may beselected from one or more of the indicated substituents. If nosubstituents are indicated, it is meant that the indicated “optionallysubstituted” or “substituted” group may be substituted with one or moregroup(s) individually and independently selected from alkyl, alkenyl,alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl,aryl(alkyl), heteroaryl(alkyl), (heterocyclyl)alkyl, hydroxy, alkoxy,acyl, cyano, halogen, thiocarbonyl, O-carbamyl, N-carbamyl,O-thiocarbamyl, N-thiocarbamyl, C-amido, N-amido, S-sulfonamido,N-sulfonamido, C-carboxy, O-carboxy, isocyanato, thiocyanato,isothiocyanato, nitro, azido, silyl, sulfenyl, sulfinyl, sulfonyl,haloalkyl, haloalkoxy, trihalomethanesulfonyl,trihalomethanesulfonamido, an amino, a mono-substituted amino group anda di-substituted amino group.

As used herein, “C_(a) to C_(b)” in which “a” and “b” are integers referto the number of carbon atoms in an alkyl, alkenyl or alkynyl group, orthe number of carbon atoms in the ring of a cycloalkyl, cycloalkenyl,aryl, heteroaryl or heterocyclyl group. That is, the alkyl, alkenyl,alkynyl, ring of the cycloalkyl, ring of the cycloalkenyl, ring of thearyl, ring of the heteroaryl or ring of the heterocyclyl can containfrom “a” to “b”, inclusive, carbon atoms. Thus, for example, a “C₁ to C₄alkyl” group refers to all alkyl groups having from 1 to 4 carbons, thatis, CH₃—, CH₃CH₂—, CH₃CH₂CH₂—, (CH₃)₂CH—, CH₃CH₂CH₂CH₂—, CH₃CH₂CH(CH₃)—and (CH₃)₃C—. If no “a” and “b” are designated with regard to an alkyl,alkenyl, alkynyl, cycloalkyl cycloalkenyl, aryl, heteroaryl orheterocyclyl group, the broadest range described in these definitions isto be assumed.

As used herein, “alkyl” refers to a straight or branched hydrocarbonchain that comprises a fully saturated (no double or triple bonds)hydrocarbon group. The alkyl group may have 1 to 20 carbon atoms(whenever it appears herein, a numerical range such as “1 to 20” refersto each integer in the given range; e.g., “1 to 20 carbon atoms” meansthat the alkyl group may consist of 1 carbon atom, 2 carbon atoms, 3carbon atoms, etc., up to and including 20 carbon atoms, although thepresent definition also covers the occurrence of the term “alkyl” whereno numerical range is designated). The alkyl group may also be a mediumsize alkyl having 1 to 10 carbon atoms. The alkyl group could also be alower alkyl having 1 to 6 carbon atoms. The alkyl group of the compoundsmay be designated as “C₁-C₄ alkyl” or similar designations. By way ofexample only, “C₁-C₄ alkyl” indicates that there are one to four carbonatoms in the alkyl chain, i.e., the alkyl chain is selected from methyl,ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl and t-butyl.Typical alkyl groups include, but are in no way limited to, methyl,ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl andhexyl. The alkyl group may be substituted or unsubstituted.

As used herein, “alkenyl” refers to an alkyl group that contains in thestraight or branched hydrocarbon chain one or more double bonds. Analkenyl group may be unsubstituted or substituted.

As used herein, “alkynyl” refers to an alkyl group that contains in thestraight or branched hydrocarbon chain one or more triple bonds. Analkynyl group may be unsubstituted or substituted.

As used herein, “cycloalkyl” refers to a completely saturated (no doubleor triple bonds) mono- or multi-cyclic hydrocarbon ring system. Whencomposed of two or more rings, the rings may be joined together in afused fashion. Cycloalkyl groups can contain 3 to 10 atoms in thering(s) or 3 to 8 atoms in the ring(s). A cycloalkyl group may beunsubstituted or substituted. Typical cycloalkyl groups include, but arein no way limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,cycloheptyl and cyclooctyl.

As used herein, “cycloalkenyl” refers to a mono- or multi-cyclichydrocarbon ring system that contains one or more double bonds in atleast one ring; although, if there is more than one, the double bondscannot form a fully delocalized pi-electron system throughout all therings (otherwise the group would be “aryl,” as defined herein). Whencomposed of two or more rings, the rings may be connected together in afused fashion. A cycloalkenyl can contain 3 to 10 atoms in the ring(s)or 3 to 8 atoms in the ring(s). A cycloalkenyl group may beunsubstituted or substituted.

As used herein, “aryl” refers to a carbocyclic (all carbon) monocyclicor multicyclic aromatic ring system (including fused ring systems wheretwo carbocyclic rings share a chemical bond) that has a fullydelocalized pi-electron system throughout all the rings. The number ofcarbon atoms in an aryl group can vary. For example, the aryl group canbe a C₆-C₁₄ aryl group, a C₆-C₁₀ aryl group, or a C₆ aryl group.Examples of aryl groups include, but are not limited to, benzene,naphthalene and azulene. An aryl group may be substituted orunsubstituted.

As used herein, “heteroaryl” refers to a monocyclic, bicyclic andtricyclicaromatic ring system (a ring system with fully delocalizedpi-electron system) that contain(s) one or more heteroatoms (forexample, 1 to 5 heteroatoms), that is, an element other than carbon,including but not limited to, nitrogen, oxygen and sulfur. The number ofatoms in the ring(s) of a heteroaryl group can vary. For example, theheteroaryl group can contain 4 to 14 atoms in the ring(s), 5 to 10 atomsin the ring(s) or 5 to 6 atoms in the ring(s). Furthermore, the term“heteroaryl” includes fused ring systems where two rings, such as atleast one aryl ring and at least one heteroaryl ring, or at least twoheteroaryl rings, share at least one chemical bond. Examples ofheteroaryl rings include, but are not limited to, furan, furazan,thiophene, benzothiophene, phthalazine, pyrrole, oxazole, benzoxazole,1,2,3-oxadiazole, 1,2,4-oxadiazole, thiazole, 1,2,3-thiadiazole,1,2,4-thiadiazole, benzothiazole, imidazole, benzimidazole, indole,indazole, pyrazole, benzopyrazole, isoxazole, benzoisoxazole,isothiazole, triazole, benzotriazole, thiadiazole, tetrazole, pyridine,pyridazine, pyrimidine, pyrazine, purine, pteridine, quinoline,isoquinoline, quinazoline, quinoxaline, cinnoline and triazine. Aheteroaryl group may be substituted or unsubstituted.

As used herein, “heterocyclyl” or “heteroalicyclyl” refers to three-,four-, five-, six-, seven-, eight-, nine-, ten-, up to 18-memberedmonocyclic, bicyclic and tricyclic ring system wherein carbon atomstogether with from 1 to 5 heteroatoms constitute said ring system. Aheterocycle may optionally contain one or more unsaturated bondssituated in such a way, however, that a fully delocalized pi-electronsystem does not occur throughout all the rings. The heteroatom(s) is anelement other than carbon including, but not limited to, oxygen, sulfurand nitrogen. A heterocycle may further contain one or more carbonyl orthiocarbonyl functionalities, so as to make the definition includeoxo-systems and thio-systems such as lactams, lactones, cyclic imides,cyclic thioimides and cyclic carbamates. When composed of two or morerings, the rings may be joined together in a fused fashion.Additionally, any nitrogens in a heterocyclyl or a heteroalicyclyl maybe quaternized. Heterocyclyl or heteroalicyclic groups may beunsubstituted or substituted. Examples of such “heterocyclyl” or“heteroalicyclyl” groups include but are not limited to, 1,3-dioxin,1,3-dioxane, 1,4-dioxane, 1,2-dioxolane, 1,3-dioxolane, 1,4-dioxolane,1,3-oxathiane, 1,4-oxathiin, 1,3-oxathiolane, 1,3-dithiole,1,3-dithiolane, 1,4-oxathiane, tetrahydro-1,4-thiazine, 2H-1,2-oxazine,maleimide, succinimide, barbituric acid, thiobarbituric acid,dioxopiperazine, hydantoin, dihydrouracil, trioxane,hexahydro-1,3,5-triazine, imidazoline, imidazolidine, isoxazoline,isoxazolidine, oxazoline, oxazolidine, oxazolidinone, thiazoline,thiazolidine, morpholine, oxirane, piperidine N-Oxide, piperidine,piperazine, pyrrolidine, pyrrolidone, pyrrolidione, 4-piperidone,pyrazoline, pyrazolidine, 2-oxopyrrolidine, tetrahydropyran, 4H-pyran,tetrahydrothiopyran, thiamorpholine, thiamorpholine sulfoxide,thiamorpholine sulfone and their benzo-fused analogs (e.g.,benzimidazolidinone, tetrahydroquinoline and 3,4-methylenedioxyphenyl).

As used herein, “aralkyl” and “aryl(alkyl)” refer to an aryl groupconnected, as a substituent, via a lower alkylene group. The loweralkylene and aryl group of an aryl(alkyl) may be substituted orunsubstituted. Examples include but are not limited to benzyl,2-phenyl(alkyl), 3-phenyl(alkyl), and naphthyl(alkyl).

As used herein, “heteroaralkyl” and “heteroaryl(alkyl)” refer to aheteroaryl group connected, as a substituent, via a lower alkylenegroup. The lower alkylene and heteroaryl group of heteroaryl(alkyl) maybe substituted or unsubstituted. Examples include but are not limited to2-thienyl(alkyl), 3-thienyl(alkyl), furyl(alkyl), thienyl(alkyl),pyrrolyl(alkyl), pyridyl(alkyl), isoxazolyl(alkyl), imidazolyl(alkyl),and their benzo-fused analogs.

A “(heteroalicyclyl)alkyl” and “(heterocyclyl)alkyl” refer to aheterocyclic or a heteroalicyclylic group connected, as a substituent,via a lower alkylene group. The lower alkylene and heterocyclyl of a(heteroalicyclyl)alkyl may be substituted or unsubstituted. Examplesinclude but are not limited tetrahydro-2H-pyran-4-yl(methyl),piperidin-4-yl(ethyl), piperidin-4-yl(propyl),tetrahydro-2H-thiopyran-4-yl(methyl) and 1,3-thiazinan-4-yl(methyl).

“Lower alkylene groups” are straight-chained —CH₂— tethering groups,forming bonds to connect molecular fragments via their terminal carbonatoms. Examples include but are not limited to methylene (—CH₂—),ethylene (—CH₂CH₂—), propylene (—CH₂CH₂CH₂—) and butylene(—CH₂CH₂CH₂CH₂—). A lower alkylene group can be substituted by replacingone or more hydrogen of the lower alkylene group with a substituent(s)listed under the definition of “substituted.”

As used herein, “alkoxy” refers to the formula —OR wherein R is analkyl, an alkenyl, an alkynyl, a cycloalkyl, a cycloalkenyl, aryl,heteroaryl, heterocyclyl, aralkyl, (heteroaryl)alkyl or(heterocyclyl)alkyl is defined herein. A non-limiting list of alkoxysare methoxy, ethoxy, n-propoxy, 1-methylethoxy (isopropoxy), n-butoxy,iso-butoxy, sec-butoxy, tert-butoxy, phenoxy and benzoxy. An alkoxy maybe substituted or unsubstituted.

As used herein, “acyl” refers to a hydrogen an alkyl, an alkenyl, analkynyl, a cycloalkyl, a cycloalkenyl, aryl, heteroaryl,heteroalicyclyl, aralkyl, heteroaryl(alkyl) or heterocyclyl(alkyl)connected, as substituents, via a carbonyl group. Examples includeformyl, acetyl, propanoyl, benzoyl, and acryl. An acyl may besubstituted or unsubstituted.

As used herein, “hydroxyalkyl” refers to an alkyl group in which one ormore of the hydrogen atoms are replaced by a hydroxy group. Exemplaryhydroxyalkyl groups include but are not limited to, 2-hydroxyethyl,3-hydroxypropyl, 2-hydroxypropyl and 2,2-dihydroxyethyl. A hydroxyalkylmay be substituted or unsubstituted.

As used herein, “haloalkyl” refers to an alkyl group in which one ormore of the hydrogen atoms are replaced by a halogen (e.g.,mono-haloalkyl, di-haloalkyl and tri-haloalkyl). Such groups include butare not limited to, chloromethyl, fluoromethyl, difluoromethyl,trifluoromethyl, 1-chloro-2-fluoromethyl and 2-fluoroisobutyl. Ahaloalkyl may be substituted or unsubstituted.

As used herein, “haloalkoxy” refers to an —O-alkyl group in which one ormore of the hydrogen atoms are replaced by a halogen (e.g.,mono-haloalkoxy, di-haloalkoxy and tri-haloalkoxy). Such groups includebut are not limited to, chloromethoxy, fluoromethoxy, difluoromethoxy,trifluoromethoxy, 1-chloro-2-fluoromethoxy and 2-fluoroisobutoxy. Ahaloalkoxy may be substituted or unsubstituted.

A “sulfenyl” group refers to an “—SR” group in which R can be hydrogen,alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl,heterocyclyl, aralkyl, (heteroaryl)alkyl or (heterocyclyl)alkyl. Asulfenyl may be substituted or unsubstituted.

A “sulfinyl” group refers to an “—S(═O)—R” group in which R can be thesame as defined with respect to sulfenyl. A sulfinyl may be substitutedor unsubstituted.

A “sulfonyl” group refers to an “SO₂R” group in which R can be the sameas defined with respect to sulfenyl. A sulfonyl may be substituted orunsubstituted.

An “O-carboxy” group refers to a “RC(═O)O—” group in which R can behydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl,heteroaryl, heterocyclyl, aralkyl, (heteroaryl)alkyl or(heterocyclyl)alkyl, as defined herein. An O-carboxy may be substitutedor unsubstituted.

The terms “ester” and “C-carboxy” refer to a “—C(═O)OR” group in which Rcan be the same as defined with respect to O-carboxy. An ester andC-carboxy may be substituted or unsubstituted.

A “thiocarbonyl” group refers to a “—C(═S)R” group in which R can be thesame as defined with respect to O-carboxy. A thiocarbonyl may besubstituted or unsubstituted.

A “trihalomethanesulfonyl” group refers to an “X₃CSO₂—” group whereineach X is a halogen.

A “trihalomethanesulfonamido” group refers to an “X₃CS(O)₂N(R_(A))—”group wherein each X is a halogen, and R_(A) is hydrogen, alkyl,alkenyl, alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl,heterocyclyl, aralkyl, (heteroaryl)alkyl or (heterocyclyl)alkyl.

The term “amino” as used herein refers to a —NH₂ group.

As used herein, the term “hydroxy” refers to a —OH group.

A “cyano” group refers to a “—CN” group.

The term “azido” as used herein refers to a —N₃ group.

An “isocyanato” group refers to a “—NCO” group.

A “thiocyanato” group refers to a “—CNS” group.

An “isothiocyanato” group refers to an “—NCS” group.

A “mercapto” group refers to an “—SH” group.

A “carbonyl” group refers to a C═O group.

An “S-sulfonamido” group refers to a “—SO₂N(R_(A)R_(B))” group in whichR_(A) and R_(B) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl. An S-sulfonamido may besubstituted or unsubstituted.

An “N-sulfonamido” group refers to a “RSO₂N(R_(A))—” group in which Rand R_(A) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl. An N-sulfonamido may besubstituted or unsubstituted.

An “O-carbamyl” group refers to a “—OC(═O)N(R_(A)R_(B))” group in whichR_(A) and R_(B) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl. An O-carbamyl may besubstituted or unsubstituted.

An “N-carbamyl” group refers to an “ROC(═O)N(R_(A))—” group in which Rand R_(A) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl. An N-carbamyl may besubstituted or unsubstituted.

An “O-thiocarbamyl” group refers to a “—OC(═S)—N(R_(A)R_(B))” group inwhich R_(A) and R_(B) can be independently hydrogen, alkyl, alkenyl,alkynyl, cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl,aralkyl, (heteroaryl)alkyl or (heterocyclyl)alkyl. An O-thiocarbamyl maybe substituted or unsubstituted.

An “N-thiocarbamyl” group refers to an “ROC(═S)N(R_(A))—” group in whichR and R_(A) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl.

An N-thiocarbamyl may be substituted or unsubstituted.

A “C-amido” group refers to a “—C(═O)N(R_(A)R_(B))” group in which R_(A)and R_(B) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl. A C-amido may be substitutedor unsubstituted.

An “N-amido” group refers to a “RC(═O)N(R_(A))—” group in which R andR_(A) can be independently hydrogen, alkyl, alkenyl, alkynyl,cycloalkyl, cycloalkenyl, aryl, heteroaryl, heterocyclyl, aralkyl,(heteroaryl)alkyl or (heterocyclyl)alkyl. An N-amido may be substitutedor unsubstituted.

The term “halogen atom” or “halogen” as used herein, means any one ofthe radio-stable atoms of column 7 of the Periodic Table of theElements, such as, fluorine, chlorine, bromine and iodine.

Where the numbers of substituents is not specified (e.g. haloalkyl),there may be one or more substituents present. For example “haloalkyl”may include one or more of the same or different halogens. As anotherexample, “C₁-C₃ alkoxyphenyl” may include one or more of the same ordifferent alkoxy groups containing one, two or three atoms.

As used herein, the abbreviations for any protective groups, amino acidsand other compounds, are, unless indicated otherwise, in accord withtheir common usage, recognized abbreviations, or the IUPAC-IUBCommission on Biochemical Nomenclature (See, Biochem. 11:942-944(1972)).

The term “nucleoside” is used herein in its ordinary sense as understoodby those skilled in the art, and refers to a compound composed of anoptionally substituted pentose moiety or modified pentose moietyattached to a heterocyclic base or tautomer thereof, such as attachedvia the 9-position of a purine-base or the 1-position of apyrimidine-base. Examples include, but are not limited to, aribonucleoside comprising a ribose moiety and a deoxyribonucleosidecomprising a deoxyribose moiety. A modified pentose moiety is a pentosemoiety in which an oxygen atom has been replaced with a carbon and/or acarbon has been replaced with a sulfur or an oxygen atom. A “nucleoside”is a monomer that can have a substituted base and/or sugar moiety.Additionally, a nucleoside can be incorporated into larger DNA and/orRNA polymers and oligomers. In some instances, the nucleoside can be anucleoside analog drug.

The term “nucleotide” is used herein in its ordinary sense as understoodby those skilled in the art, and refers to a nucleoside having aphosphate ester bound to the pentose moiety, for example, at the5′-position.

As used herein, the term “heterocyclic base” refers to an optionallysubstituted nitrogen-containing heterocyclyl that can be attached to anoptionally substituted pentose moiety or modified pentose moiety. Insome embodiments, the heterocyclic base can be selected from anoptionally substituted purine-base, an optionally substitutedpyrimidine-base and an optionally substituted triazole-base (forexample, a 1,2,4-triazole). The term “purine-base” is used herein in itsordinary sense as understood by those skilled in the art, and includesits tautomers. Similarly, the term “pyrimidine-base” is used herein inits ordinary sense as understood by those skilled in the art, andincludes its tautomers. A non-limiting list of optionally substitutedpurine-bases includes purine, adenine, guanine, hypoxanthine, xanthine,alloxanthine, 7-alkylguanine (e.g. 7-methylguanine), theobromine,caffeine, uric acid and isoguanine. Examples of pyrimidine-basesinclude, but are not limited to, cytosine, thymine, uracil,5,6-dihydrouracil and 5-alkylcytosine (e.g., 5-methylcytosine). Anexample of an optionally substituted triazole-base is1,2,4-triazole-3-carboxamide. Other non-limiting examples ofheterocyclic bases include diaminopurine, 8-oxo-N⁶-alkyladenine (e.g.,8-oxo-N⁶-methyladenine), 7-deazaxanthine, 7-deazaguanine,7-deazaadenine, N⁴,N⁴-ethanocytosin, N⁶,N⁶-ethano-2,6-diaminopurine,5-halouracil (e.g., 5-fluorouracil and 5-bromouracil),pseudoisocytosine, isocytosine, isoguanine, and other heterocyclic basesdescribed in U.S. Pat. Nos. 5,432,272 and 7,125,855, which areincorporated herein by reference for the limited purpose of disclosingadditional heterocyclic bases. In some embodiments, a heterocyclic basecan be optionally substituted with an amine or an enol protectinggroup(s).

The term “—N-linked amino acid” refers to an amino acid that is attachedto the indicated moiety via a main-chain amino or mono-substituted aminogroup. When the amino acid is attached in an —N-linked amino acid, oneof the hydrogens that is part of the main-chain amino ormono-substituted amino group is not present and the amino acid isattached via the nitrogen. N-linked amino acids can be substituted orunsubstituted.

The term “—N-linked amino acid ester derivative” refers to an amino acidin which a main-chain carboxylic acid group has been converted to anester group. In some embodiments, the ester group has a formula selectedfrom alkyl-O—C(═O)—, cycloalkyl-O—C(═O)—, aryl-O—C(═O)— andaryl(alkyl)-O—C(═O)—. A non-limiting list of ester groups includesubstituted and unsubstituted versions of the following:methyl-O—C(═O)—, ethyl-O—C(═O)—, n-propyl-O—C(═O)—, isopropyl-O—C(═O)—,n-butyl-O—C(═O)—, isobutyl-O—C(═O)—, tert-butyl-O—C(═O)—,neopentyl-O—C(═O)—, cyclopropyl-O—C(═O)—, cyclobutyl-O—C(═O)—,cyclopentyl-O—C(═O)—, cyclohexyl-O—C(═O)—, phenyl-O—C(═O)—,benzyl-O—C(═O)— and naphthyl-O—C(═O)—. N-linked amino acid esterderivatives can be substituted or unsubstituted.

The term “—O-linked amino acid” refers to an amino acid that is attachedto the indicated moiety via the hydroxy from its main-chain carboxylicacid group. When the amino acid is attached in an —O-linked amino acid,the hydrogen that is part of the hydroxy from its main-chain carboxylicacid group is not present and the amino acid is attached via the oxygen.O-linked amino acids can be substituted or unsubstituted.

As used herein, the term “amino acid” refers to any amino acid (bothstandard and non-standard amino acids), including, but not limited to,α-amino acids, β-amino acids, γ-amino acids and δ-amino acids. Examplesof suitable amino acids include, but are not limited to, alanine,asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline,serine, tyrosine, arginine, histidine, isoleucine, leucine, lysine,methionine, phenylalanine, threonine, tryptophan and valine. Additionalexamples of suitable amino acids include, but are not limited to,ornithine, hypusine, 2-aminoisobutyric acid, dehydroalanine,gamma-aminobutyric acid, citrulline, beta-alanine, alpha-ethyl-glycine,alpha-propyl-glycine and norleucine.

The terms “phosphorothioate” and “phosphothioate” refer to a compound ofthe general formula

its protonated forms (for example,

) and its tautomers (such as

).

As used herein, the term “phosphate” is used in its ordinary sense asunderstood by those skilled in the art, and includes its protonatedforms (for example,

). As used herein, the terms “monophosphate,” “diphosphate,” and“triphosphate” are used in their ordinary sense as understood by thoseskilled in the art, and include protonated forms.

The terms “protecting group” and “protecting groups” as used hereinrefer to any atom or group of atoms that is added to a molecule in orderto prevent existing groups in the molecule from undergoing unwantedchemical reactions. Examples of protecting group moieties are describedin T. W. Greene and P. G. M. Wuts, Protective Groups in OrganicSynthesis, 3. Ed. John Wiley & Sons, 1999, and in J. F. W. McOmie,Protective Groups in Organic Chemistry Plenum Press, 1973, both of whichare hereby incorporated by reference for the limited purpose ofdisclosing suitable protecting groups. The protecting group moiety maybe chosen in such a way, that they are stable to certain reactionconditions and readily removed at a convenient stage using methodologyknown from the art. A non-limiting list of protecting groups includebenzyl; substituted benzyl; alkylcarbonyls and alkoxycarbonyls (e.g.,t-butoxycarbonyl (BOC), acetyl, or isobutyryl); arylalkylcarbonyls andarylalkoxycarbonyls (e.g., benzyloxycarbonyl); substituted methyl ether(e.g. methoxymethyl ether); substituted ethyl ether; a substitutedbenzyl ether; tetrahydropyranyl ether; silyls (e.g., trimethylsilyl,triethylsilyl, triisopropylsilyl, t-butyldimethylsilyl,tri-iso-propylsilyloxymethyl, [2-(trimethylsilyl)ethoxy]methyl ort-butyldiphenylsilyl); esters (e.g. benzoate ester); carbonates (e.g.methoxymethylcarbonate); sulfonates (e.g. tosylate or mesylate); acyclicketal (e.g. dimethyl acetal); cyclic ketals (e.g., 1,3-dioxane,1,3-dioxolanes and those described herein); acyclic acetal; cyclicacetal (e.g., those described herein); acyclic hemiacetal; cyclichemiacetal; cyclic dithioketals (e.g., 1,3-dithiane or 1,3-dithiolane);orthoesters (e.g., those described herein) and triarylmethyl groups(e.g., trityl; monomethoxytrityl (MMTr); 4,4′-dimethoxytrityl (DMTr);4,4′,4″-trimethoxytrityl (TMTr); and those described herein).

The term “pharmaceutically acceptable salt” refers to a salt of acompound that does not cause significant irritation to an organism towhich it is administered and does not abrogate the biological activityand properties of the compound. In some embodiments, the salt is an acidaddition salt of the compound. Pharmaceutical salts can be obtained byreacting a compound with inorganic acids such as hydrohalic acid (e.g.,hydrochloric acid or hydrobromic acid), sulfuric acid, nitric acid andphosphoric acid. Pharmaceutical salts can also be obtained by reacting acompound with an organic acid such as aliphatic or aromatic carboxylicor sulfonic acids, for example formic, acetic, succinic, lactic, malic,tartaric, citric, ascorbic, nicotinic, methanesulfonic, ethanesulfonic,p-toluenesulfonic, salicylic or naphthalenesulfonic acid. Pharmaceuticalsalts can also be obtained by reacting a compound with a base to form asalt such as an ammonium salt, an alkali metal salt, such as a sodium ora potassium salt, an alkaline earth metal salt, such as a calcium or amagnesium salt, a salt of organic bases such as dicyclohexylamine,N-methyl-D-glucamine, tris(hydroxymethyl)methylamine, C₁-C₇ alkylamine,cyclohexylamine, triethanolamine, ethylenediamine, and salts with aminoacids such as arginine and lysine.

Terms and phrases used in this application, and variations thereof,especially in the appended claims, unless otherwise expressly stated,should be construed as open ended as opposed to limiting. As examples ofthe foregoing, the term ‘including’ should be read to mean ‘including,without limitation,’ ‘including but not limited to,’ or the like; theterm ‘comprising’ as used herein is synonymous with ‘including,’‘containing,’ or ‘characterized by,’ and is inclusive or open-ended anddoes not exclude additional, unrecited elements or method steps; theterm ‘having’ should be interpreted as ‘having at least;’ the term‘includes’ should be interpreted as ‘includes but is not limited to;’the term ‘example’ is used to provide exemplary instances of the item indiscussion, not an exhaustive or limiting list thereof; and use of termslike ‘preferably,’ ‘preferred,’ ‘desired,’ or ‘desirable,’ and words ofsimilar meaning should not be understood as implying that certainfeatures are critical, essential, or even important to the structure orfunction, but instead as merely intended to highlight alternative oradditional features that may or may not be utilized in a particularembodiment. In addition, the term “comprising” is to be interpretedsynonymously with the phrases “having at least” or “including at least”.When used in the context of a process, the term “comprising” means thatthe process includes at least the recited steps, but may includeadditional steps. When used in the context of a compound, composition ordevice, the term “comprising” means that the compound, composition ordevice includes at least the recited features or components, but mayalso include additional features or components. Likewise, a group ofitems linked with the conjunction ‘and’ should not be read as requiringthat each and every one of those items be present in the grouping, butrather should be read as ‘and/or’ unless expressly stated otherwise.Similarly, a group of items linked with the conjunction ‘or’ should notbe read as requiring mutual exclusivity among that group, but rathershould be read as ‘and/or’ unless expressly stated otherwise.

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art can translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations may be expressly set forth herein for sakeof clarity. The indefinite article “a” or “an” does not exclude aplurality. A single processor or other unit may fulfill the functions ofseveral items recited in the claims. The mere fact that certain measuresare recited in mutually different dependent claims does not indicatethat a combination of these measures cannot be used to advantage. Anyreference signs in the claims should not be construed as limiting thescope.

It is understood that, in any compound described herein having one ormore chiral centers, if an absolute stereochemistry is not expresslyindicated, then each center may independently be of R-configuration orS-configuration or a mixture thereof. Thus, the compounds providedherein may be enantiomerically pure, enantiomerically enriched, racemicmixture, diastereomerically pure, diastereomerically enriched, or astereoisomeric mixture. In addition it is understood that, in anycompound described herein having one or more double bond(s) generatinggeometrical isomers that can be defined as E or Z, each double bond mayindependently be E or Z a mixture thereof.

Likewise, it is understood that, in any compound described, alltautomeric forms are also intended to be included. For example alltautomers of a phosphate and a phosphorothioate groups are intended tobe included. Examples of tautomers of a phosphorothioate include thefollowing:

Furthermore, all tautomers of heterocyclic bases known in the art areintended to be included, including tautomers of natural and non-naturalpurine-bases and pyrimidine-bases.

It is to be understood that where compounds disclosed herein haveunfilled valencies, then the valencies are to be filled with hydrogensor isotopes thereof, e.g., hydrogen-1 (protium) and hydrogen-2(deuterium).

It is understood that the compounds described herein can be labeledisotopically. Substitution with isotopes such as deuterium may affordcertain therapeutic advantages resulting from greater metabolicstability, such as, for example, increased in vivo half-life or reduceddosage requirements. Each chemical element as represented in a compoundstructure may include any isotope of said element. For example, in acompound structure a hydrogen atom may be explicitly disclosed orunderstood to be present in the compound. At any position of thecompound that a hydrogen atom may be present, the hydrogen atom can beany isotope of hydrogen, including but not limited to hydrogen-1(protium) and hydrogen-2 (deuterium). Thus, reference herein to acompound encompasses all potential isotopic forms unless the contextclearly dictates otherwise.

It is understood that the methods and combinations described hereininclude crystalline forms (also known as polymorphs, which include thedifferent crystal packing arrangements of the same elemental compositionof a compound), amorphous phases, salts, solvates and hydrates. In someembodiments, the compounds described herein exist in solvated forms withpharmaceutically acceptable solvents such as water, ethanol, or thelike. In other embodiments, the compounds described herein exist inunsolvated form. Solvates contain either stoichiometric ornon-stoichiometric amounts of a solvent, and may be formed during theprocess of crystallization with pharmaceutically acceptable solventssuch as water, ethanol, or the like. Hydrates are formed when thesolvent is water, or alcoholates are formed when the solvent is alcohol.In addition, the compounds provided herein can exist in unsolvated aswell as solvated forms. In general, the solvated forms are consideredequivalent to the unsolvated forms for the purposes of the compounds andmethods provided herein.

Where a range of values is provided, it is understood that the upper andlower limit, and each intervening value between the upper and lowerlimit of the range is encompassed within the embodiments.

Methods of Use

Some embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Coronaviridae virus that caninclude administering to a subject an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes a compound described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Other embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Coronaviridae virus that caninclude administering to a subject identified as suffering from theviral infection an effective amount of one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof), or a pharmaceutical composition that includesa compound described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

Some embodiments described herein relate to using one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for ameliorating and/or treating an infection caused by aCoronaviridae virus that can include administering to a subject aneffective amount of one or more compounds described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Still other embodiments described herein relate to one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof) that can be used forameliorating and/or treating an infection caused by a Coronaviridaevirus by administering to a subject an effective amount of one or morecompounds described herein.

Some embodiments disclosed herein relate to methods of amelioratingand/or treating an infection caused by a Coronaviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), or apharmaceutical composition that includes one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof). Other embodiments described herein relate tousing one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), in themanufacture of a medicament for ameliorating and/or treating aninfection caused by a Coronaviridae virus that can include contacting acell infected with the virus with an effective amount of saidcompound(s). Still other embodiments described herein relate to one ormore compounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), that can be used forameliorating and/or treating an infection caused by a Coronaviridaevirus by contacting a cell infected with the virus with an effectiveamount of said compound(s).

Some embodiments disclosed herein relate to methods of inhibitingreplication of a Coronaviridae virus that can include contacting a cellinfected with the virus with an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein (suchas a compound of Formula (I), or a pharmaceutically acceptable saltthereof). Other embodiments described herein relate to using one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for inhibiting replication of a Coronaviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to a compound described herein (such as a compound of Formula(I), or a pharmaceutically acceptable salt thereof), that can be usedfor inhibiting replication of a Coronaviridae virus by contacting a cellinfected with the virus with an effective amount of said compound(s). Insome embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can inhibit a RNA dependent RNA polymerase of aCoronaviridae virus, and thus, inhibit the replication of RNA. In someembodiments, a polymerase of a Coronaviridae virus can be inhibited bycontacting a cell infected with the Coronaviridae virus with a compounddescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

In some embodiments, the Coronaviridae virus can be a Coronavirus. Inother embodiments, the Coronaviridae virus can be a Torovirus. In someembodiments, a compound described herein (for example, a compound ofFormula (I), or a pharmaceutical acceptable salt thereof) can ameliorateand/or treat a Coronavirus infection. For example, by administering aneffective amount of a compound of Formula (I), or a pharmaceuticalacceptable salt thereof, to a subject infected with the Coronavirusand/or by contacting a cell infected with the Coronavirus. In someembodiments, a compound described herein (for example, a compound ofFormula (I), or a pharmaceutical acceptable salt thereof) can inhibitreplication of a Coronavirus. In some embodiments, a compound of Formula(I), or a pharmaceutical acceptable salt thereof, can be effectiveagainst a Coronavirus, and thereby ameliorate one or more symptoms of aCoronavirus infection.

There are several species within the Coronavirus genus including, butnot limited to, Middle East respiratory syndrome coronavirus (MERS-CoV)and SARS coronavirus (SARS-CoV). In some embodiments, a compounddescribed herein (for example, a compound of Formula (I), or apharmaceutical acceptable salt thereof) can ameliorate and/or treat aMERS-CoV infection. For example, by administering an effective amount ofa compound of Formula (I), or a pharmaceutical acceptable salt thereof,to a subject infected with MERS-CoV and/or by contacting a cell infectedwith MERS-CoV. In some embodiments, a compound described herein (forexample, a compound of Formula (I), or a pharmaceutical acceptable saltthereof) can inhibit replication of MERS-CoV. In some embodiments, acompound of Formula (I), or a pharmaceutical acceptable salt thereof,can be effective against MERS-CoV, and thereby ameliorate one or moresymptoms of a MERS-CoV infection. Symptoms of MERS-CoV include, but arenot limited to, fever (e.g., >100.4° F.), cough, shortness of breath,renal failure, diarrhea, breathing difficulties and pneumonia.

In some embodiments, a compound described herein (for example, acompound of Formula (I), or a pharmaceutical acceptable salt thereof)can ameliorate and/or treat a SARS-CoV infection. An effective amount ofa compound of Formula (I), or a pharmaceutical acceptable salt thereof,can be administered to a subject infected with SARS-CoV and/or bycontacting a cell infected with SARS-CoV with an effective amount of acompound of Formula (I), or a pharmaceutical acceptable salt thereof. Insome embodiments, a compound described herein (for example, a compoundof Formula (I), or a pharmaceutical acceptable salt thereof) can inhibitreplication of SARS-CoV. In some embodiments, a compound of Formula (I),or a pharmaceutical acceptable salt thereof, can be effective againstSARS-CoV, and thereby ameliorate one or more symptoms of a SARS-CoVinfection. Symptoms of SARS-CoV include, but are not limited to, extremefatigue, malaise, headache, high fever (e.g., >100.4° F.), lethargy,confusion, rash, loss of appetite, myalgia, chills, diarrhea, dry cough,runny nose, sore throat, shortness of breath, breathing problems,gradual fall in blood-oxygen levels (such as, hypoxia) and pneumonia.

In some embodiments, a compound described herein (for example, acompound of Formula (I), or a pharmaceutical acceptable salt thereof)can ameliorate and/or treat a Torovirus infection. In some embodiments,a Torovirus infection can be ameliorated and/or treated by administeringan effective amount of a compound of Formula (I), or a pharmaceuticalacceptable salt thereof, to a subject infected with the Torovirus and/orby contacting a cell infected with the Torovirus. In some embodiments, acompound described herein (for example, a compound of Formula (I), or apharmaceutical acceptable salt thereof) can inhibit replication of aTorovirus. In some embodiments, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can ameliorate one or moresymptoms of a Torovirus infection.

Some embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Togaviridae virus that can includeadministering to a subject an effective amount of one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes a compound described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Other embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Togaviridae virus that can includeadministering to a subject identified as suffering from the viralinfection an effective amount of one or more compounds described herein(such as a compound of Formula (I), or a pharmaceutically acceptablesalt thereof), or a pharmaceutical composition that includes a compounddescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

Some embodiments described herein relate to using one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for ameliorating and/or treating an infection caused by aTogaviridae virus that can include administering to a subject aneffective amount of one or more compounds described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Still other embodiments described herein relate to one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof) that can be used forameliorating and/or treating an infection caused by a Togaviridae virusby administering to a subject an effective amount of one or morecompounds described herein.

Some embodiments disclosed herein relate to methods of amelioratingand/or treating an infection caused by a Togaviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), or apharmaceutical composition that includes one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof). Other embodiments described herein relate tousing one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), in themanufacture of a medicament for ameliorating and/or treating aninfection caused by a Togaviridae virus that can include contacting acell infected with the virus with an effective amount of saidcompound(s). Still other embodiments described herein relate to one ormore compounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), that can be used forameliorating and/or treating an infection caused by a Togaviridae virusby contacting a cell infected with the virus with an effective amount ofsaid compound(s).

Some embodiments disclosed herein relate to methods of inhibitingreplication of a Togaviridae virus that can include contacting a cellinfected with the virus with an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein (suchas a compound of Formula (I), or a pharmaceutically acceptable saltthereof). Other embodiments described herein relate to using one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for inhibiting replication of a Togaviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to a compound described herein (such as a compound of Formula(I), or a pharmaceutically acceptable salt thereof), that can be usedfor inhibiting replication of a Togaviridae virus by contacting a cellinfected with the virus with an effective amount of said compound(s). Insome embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can inhibit a RNA dependent RNA polymerase of aTogaviridae virus, and thereby, inhibit the replication of RNA. In someembodiments, a polymerase of a Togaviridae virus can be inhibited bycontacting a cell infected with the Togaviridae virus with a compounddescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

In some embodiments, the Togaviridae virus can be an Alphavirus. Onespecies of an Alphavirus is a Venezuelan equine encephalitis virus(VEEV). In some embodiments, a compound described herein (for example, acompound of Formula (I), or a pharmaceutical acceptable salt thereof)can ameliorate and/or treat a VEEV infection. In other embodiments, oneor more compounds described herein (such as a compound of Formula (I),or a pharmaceutically acceptable salt thereof), can be manufactured intoa medicament for ameliorating and/or treating an infection caused by aVEEV that can include contacting a cell infected with the virus with aneffective amount of said compound(s). In still other embodiments, one ormore compounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), can be used for amelioratingand/or treating an infection caused by a VEEV that can includecontacting a cell infected with the virus with an effective amount ofsaid compound(s). In some embodiment, the VEEV can be an epizooticsubtype. In some embodiment, the VEEV can be an enzootic subtype. Asdescribed herein, the Venezuelan equine encephalitis complex of virusesincludes multiple subtypes that are further divided by antigenicvariants. In some embodiments, a compound described herein (for example,a compound of Formula (I), or a pharmaceutical acceptable salt thereof)can be effective against more than one subtype of a VEEV, such as 2, 3,4, 5 or 6 subtypes. In some embodiments, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can be used to treat, ameliorateand/or prevent VEEV subtype I. In some embodiments, a compound describedherein (for example, a compound of Formula (I), or a pharmaceuticalacceptable salt thereof) can be effective against more than oneantigenic variants of a VEEV. In some embodiments, a compound of Formula(I), or a pharmaceutical acceptable salt thereof, can ameliorate one ormore symptoms of a VEEV infection. Examples of symptoms manifested by asubject infected with VEEV include flu-like symptoms, such as highfever, headache, myalgia, fatigue, vomiting, nausea, diarrhea, andpharyngitis. Subjects with encephalitis show one or more of thefollowing symptoms: somnolence, convulsions, confusion, photophobia,coma and bleeding of the brain, lung(s) and/or gastrointestinal tract.In some embodiments, the subject can be human. In other embodiments, thesubject can be a horse.

Chikungunya (CHIKV) is another Alphavirus species. In some embodiments,a compound described herein (for example, a compound of Formula (I), ora pharmaceutical acceptable salt thereof) can ameliorate and/or treat aCHIKV infection. In other embodiments, one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof), can be manufactured into a medicament forameliorating and/or treating an infection caused by a CHIKV that caninclude contacting a cell infected with the virus with an effectiveamount of said compound(s). In still other embodiments, one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), can be used for amelioratingand/or treating an infection caused by a CHIKV that can includecontacting a cell infected with the virus with an effective amount ofsaid compound(s). In some embodiments, one or more symptoms of a CHIKVinfection can be ameliorated by administering an effective amount of acompound of Formula (I), or a pharmaceutical acceptable salt thereof, toa subject infected with CHIKV and/or by contacting an CHIKV infectedcell with an effective amount of a compound of Formula (I), or apharmaceutical acceptable salt thereof. Clinical symptoms of a CHIKVinfection include fever, rash (such as petechial and/or maculopapularrash), muscle pain, joint pain, fatigue, headache, nausea, vomiting,conjunctivitis, loss of taste, photophobia, insomnia, incapacitatingjoint pain and arthritis.

Other species of Alphaviruses include Barmah Forest virus, Mayaro virus(MAYV), O'nyong'nyong virus, Ross River virus (RRV), Semliki Forestvirus, Sindbis virus (SINV), Una virus, Eastern equine encephalitisvirus (EEE) and Western equine encephalomyelitis (WEE). In someembodiments, one or more compounds described herein (such as a compoundof Formula (I), or a pharmaceutically acceptable salt thereof), can beused for ameliorating and/or treating an infection caused by anAlphavirus that can include contacting a cell infected with the viruswith an effective amount of one or more of said compound(s) and/oradministering to a subject (such as, a subject infected with the virus)an effective amount of one or more of said compound(s), wherein theAlphavirus can be selected from Barmah Forest virus, Mayaro virus(MAYV), O'nyong'nyong virus, Ross River virus (RRV), Semliki Forestvirus, Sindbis virus (SINV), Una virus, Eastern equine encephalitisvirus (EEE) and Western equine encephalomyelitis (WEE).

Another genus of a Coronaviridae virus is a Rubivirus. Some embodimentsdisclosed herein relate to methods of ameliorating and/or treating aninfection caused by a Rubivirus that can include contacting a cellinfected with the virus with an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein (suchas a compound of Formula (I), or a pharmaceutically acceptable saltthereof). Other embodiments described herein relate to using one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for ameliorating and/or treating an infection caused by aRubivirus that can include contacting a cell infected with the viruswith an effective amount of said compound(s). Still other embodimentsdescribed herein relate to one or more compounds described herein (suchas a compound of Formula (I), or a pharmaceutically acceptable saltthereof), that can be used for ameliorating and/or treating an infectioncaused by a Rubivirus by contacting a cell infected with the virus withan effective amount of said compound(s).

Some embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Hepeviridae virus that can includeadministering to a subject an effective amount of one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes a compound described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Other embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Hepeviridae virus that can includeadministering to a subject identified as suffering from the viralinfection an effective amount of one or more compounds described herein(such as a compound of Formula (I), or a pharmaceutically acceptablesalt thereof), or a pharmaceutical composition that includes a compounddescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

Some embodiments described herein relate to using one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for ameliorating and/or treating an infection caused by aHepeviridae virus that can include administering to a subject aneffective amount of one or more compounds described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Still other embodiments described herein relate to one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof) that can be used forameliorating and/or treating an infection caused by a Hepeviridae virusby administering to a subject an effective amount of one or morecompounds described herein.

Some embodiments disclosed herein relate to methods of amelioratingand/or treating an infection caused by a Hepeviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), or apharmaceutical composition that includes one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof). Other embodiments described herein relate tousing one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), in themanufacture of a medicament for ameliorating and/or treating aninfection caused by a Hepeviridae virus that can include contacting acell infected with the virus with an effective amount of saidcompound(s). Still other embodiments described herein relate to one ormore compounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), that can be used forameliorating and/or treating an infection caused by a Hepeviridae virusby contacting a cell infected with the virus with an effective amount ofsaid compound(s).

Some embodiments disclosed herein relate to methods of inhibitingreplication of a Hepeviridae virus that can include contacting a cellinfected with the virus with an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein (suchas a compound of Formula (I), or a pharmaceutically acceptable saltthereof). Other embodiments described herein relate to using one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for inhibiting replication of a Hepeviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to a compound described herein (such as a compound of Formula(I), or a pharmaceutically acceptable salt thereof), that can be usedfor inhibiting replication of a Hepeviridae virus by contacting a cellinfected with the virus with an effective amount of said compound(s). Insome embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can inhibit a RNA dependent RNA polymerase of aHepeviridae virus, and thus, inhibit the replication of RNA. In someembodiments, a polymerase of a Hepeviridae virus can be inhibited bycontacting a cell infected with the Hepeviridae virus with a compounddescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

In some embodiments, the Hepeviridae virus can be a Hepevirus, such as aHepatitis E virus. In some embodiments, a compound described herein (forexample, a compound of Formula (I), or a pharmaceutical acceptable saltthereof) can ameliorate and/or treat a Hepatitis E virus infection. Inother embodiments, one or more compounds described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof),can be manufactured into a medicament for ameliorating and/or treatingan infection caused by a Hepatitis E virus that can include contacting acell infected with the virus with an effective amount of saidcompound(s). In still other embodiments, one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof), can be used for ameliorating and/or treatingan infection caused by a Hepatitis E virus that can include contacting acell infected with the virus with an effective amount of saidcompound(s). Hepatitis E includes several genotypes, as describedherein, and each genotype includes several subtypes. In someembodiments, a compound described herein (for example, a compound ofFormula (I), or a pharmaceutical acceptable salt thereof) can beeffective against one or more genotypes of Hepatitis E virus, such as 1,2, 3 or 4 genotypes. In some embodiments, a compound of Formula (I), ora pharmaceutical acceptable salt thereof, can be effective one or moresubtypes of Hepatitis E. For example, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can be effective against 2 ormore, 3 or more, or more than 4 subtypes of Hepatitis E. In someembodiments, a compound of Formula (I), or a pharmaceutical acceptablesalt thereof, can be effective against a Hepatitis E virus, and therebyameliorate one or more symptoms of a Hepatitis E infection. Symptoms ofa Hepatitis E virus infection include, but are not limited to, acutesporadic hepatitis, epidemic viral hepatitis, jaundice, anorexia,hepatomegaly, abdominal pain and/or tenderness, nausea, vomiting, fever,fatigue, diarrhea and dark urine.

A Hepatitis E infection can also affect the liver. In some embodiments,a compound described herein (for example, a compound of Formula (I), ora pharmaceutical acceptable salt thereof) can be used to treat and/orameliorate a liver condition associated with a Hepatitis E virusinfection. Some embodiments described herein relate to a method oftreating a condition selected from liver fibrosis, liver cirrhosis andliver cancer in a subject suffering from one or more of theaforementioned liver conditions that can include administering to thesubject an effective amount of a compound or a pharmaceuticalcomposition described herein (for example, a compound of Formula (I), ora pharmaceutically acceptable salt thereof), wherein the liver conditionis caused by a Hepatitis E virus infection. Some embodiments describedherein relate to a method of increasing liver function in a subjecthaving a Hepatitis E virus infection that can include administering tothe subject an effective amount of a compound or a pharmaceuticalcomposition described herein (for example, a compound of Formula (I), ora pharmaceutically acceptable salt thereof). Also contemplated is amethod for reducing or eliminating further virus-caused liver damage ina subject having a Hepatitis E virus infection by administering to thesubject an effective amount of a compound or a pharmaceuticalcomposition described herein (for example, a compound of Formula (I), ora pharmaceutically acceptable salt thereof). In some embodiments, thismethod can include slowing or halting the progression of liver disease.In other embodiments, the course of the disease can be reversed, andstasis or improvement in liver function is contemplated. In someembodiments, liver fibrosis, liver cirrhosis and/or liver cancer can betreated; liver function can be increased; virus-caused liver damage canbe reduced or eliminated; progression of liver disease can be slowed orhalted; the course of the liver disease can be reversed and/or liverfunction can be improved or maintained by contacting a cell infectedwith a Hepatitis E virus with an effective amount of a compounddescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt of the foregoing).

Some embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Bunyaviridae virus that caninclude administering to a subject an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes a compound described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Other embodiments disclosed herein relate to a method of treating and/orameliorating an infection caused by a Bunyaviridae virus that caninclude administering to a subject identified as suffering from theviral infection an effective amount of one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof), or a pharmaceutical composition that includesa compound described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

Some embodiments described herein relate to using one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for ameliorating and/or treating an infection caused by aBunyaviridae virus that can include administering to a subject aneffective amount of one or more compounds described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof).Still other embodiments described herein relate to one or more compoundsdescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof) that can be used forameliorating and/or treating an infection caused by a Bunyaviridae virusby administering to a subject an effective amount of one or morecompounds described herein.

Some embodiments disclosed herein relate to methods of amelioratingand/or treating an infection caused by a Bunyaviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), or apharmaceutical composition that includes one or more compounds describedherein (such as a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof). Other embodiments described herein relate tousing one or more compounds described herein (such as a compound ofFormula (I), or a pharmaceutically acceptable salt thereof), in themanufacture of a medicament for ameliorating and/or treating aninfection caused by a Bunyaviridae virus that can include contacting acell infected with the virus with an effective amount of saidcompound(s). Still other embodiments described herein relate to one ormore compounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), that can be used forameliorating and/or treating an infection caused by a Bunyaviridae virusby contacting a cell infected with the virus with an effective amount ofsaid compound(s).

Some embodiments disclosed herein relate to methods of inhibitingreplication of a Bunyaviridae virus that can include contacting a cellinfected with the virus with an effective amount of one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), or a pharmaceuticalcomposition that includes one or more compounds described herein (suchas a compound of Formula (I), or a pharmaceutically acceptable saltthereof). Other embodiments described herein relate to using one or morecompounds described herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof), in the manufacture of amedicament for inhibiting replication of a Bunyaviridae virus that caninclude contacting a cell infected with the virus with an effectiveamount of said compound(s). Still other embodiments described hereinrelate to a compound described herein (such as a compound of Formula(I), or a pharmaceutically acceptable salt thereof), that can be usedfor inhibiting replication of a Bunyaviridae virus by contacting a cellinfected with the virus with an effective amount of said compound(s). Insome embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can inhibit a RNA dependent RNA polymerase of aBunyaviridae virus, and thereby, inhibit the replication of RNA. In someembodiments, a polymerase of a Bunyaviridae virus can be inhibited bycontacting a cell infected with the Bunyaviridae virus with a compounddescribed herein (such as a compound of Formula (I), or apharmaceutically acceptable salt thereof).

In some embodiments, the Bunyaviridae virus can be a Bunyavirus. Inother embodiments, the Bunyaviridae virus can be a Hantavirus. In stillother embodiments, the Bunyaviridae virus can be a Nairovirus. In yetstill other embodiments, the Bunyaviridae virus can be a Phlebovirus. Insome embodiments, the Bunyaviridae virus can be an Orthobunyavirus. Inother embodiments, the Bunyaviridae virus can be a Tospovirus.

A species of the Phlebovirus genus is Rift Valley Fever virus. In someembodiments, a compound described herein (for example, a compound ofFormula (I), or a pharmaceutical acceptable salt thereof) can ameliorateand/or treat a Rift Valley Fever virus infection. In other embodiments,one or more compounds described herein (such as a compound of Formula(I), or a pharmaceutically acceptable salt thereof), can be manufacturedinto a medicament for ameliorating and/or treating an infection causedby a Rift Valley Fever virus that can include contacting a cell infectedwith the virus with an effective amount of said compound(s). In stillother embodiments, one or more compounds described herein (such as acompound of Formula (I), or a pharmaceutically acceptable salt thereof),can be used for ameliorating and/or treating an infection caused by aRift Valley Fever virus that can include contacting a cell infected withthe virus with an effective amount of said compound(s). In someembodiments, a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, can inhibit replication of Rift Valley Fever virus,wherein said compound is administering to a subject infected with RiftValley Fever virus and/or wherein said compound contacts a cell infectedwith Rift Valley Fever.

In some embodiments, a compound of Formula (I), or a pharmaceuticalacceptable salt thereof, can ameliorate, treat, and/or inhibitreplication of the ocular form of Rift Valley Fever virus. In someembodiments, a compound of Formula (I), or a pharmaceutical acceptablesalt thereof, can ameliorate, treat, and/or inhibit replication of themeningoencephalitis form of Rift Valley Fever virus. In someembodiments, a compound of Formula (I), or a pharmaceutical acceptablesalt thereof, can ameliorate, treat, and/or inhibit replication of thehemorrhagic fever form of Rift Valley Fever virus. In some embodiments,a compound of Formula (I), or a pharmaceutical acceptable salt thereof,can be effective against one or more forms of Rift Valley Fever virus.In some embodiments, one or more symptoms of a Rift Valley Fever virusinfection can be ameliorated by a compound of Formula (I), or apharmaceutical acceptable salt thereof, wherein an effective amount ofsaid compound is administered to an infected subject and/or an effectiveamount of said compound contacts an infected cell. Examples of symptomsof a Rift Valley Fever viral infection include headache, muscle pain,joint pain, neck stiffness, sensitivity to light, loss of appetite,vomiting, myalgia, fever, fatigue, back pain, dizziness, weight loss,ocular form symptoms (for example, retinal lesions, blurred vision,decreased vision and/or permanent loss of vision), meningoencephalitisform symptoms (such as, intense headache, loss of memory,hallucinations, confusion, disorientation, vertigo, convulsions,lethargy and coma) and hemorrhagic fever form symptoms (for example,jaundice, vomiting blood, passing blood in the feces, a purpuric rash,ecchymoses, bleeding from the nose and/or gums, menorrhagia and bleedingfrom a venepuncture site).

Another species of the Phlebovirus genus is thrombocytopenia syndromevirus. In some embodiments, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can ameliorate, treat, and/orinhibit replication thrombocytopenia syndrome virus. In someembodiments, a compound of Formula (I), or a pharmaceutical acceptablesalt thereof, can ameliorate and/or treat severe fever withthrombocytopenia syndrome (SFTS). In some embodiments, a compound ofFormula (I), or a pharmaceutical acceptable salt thereof, can ameliorateone or more symptoms of SFTS. Clinical symptoms of include thefollowing: fever, vomiting, diarrhea, multiple organ failure,thrombocytopenia, leucopenia, and elevated liver enzyme levels.

Crimean-Congo hemorrhagic fever virus (CCHF) is a species within theNairovirus genus. In some embodiments, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can ameliorate, treat, and/orinhibit replication of Crimean-Congo hemorrhagic fever virus. Subjectsinfected with CCHF have one or more of the following symptoms: flu-likesymptoms (such as high fever, headache, myalgia, fatigue, vomiting,nausea, diarrhea, and/or pharyngitis), hemorrhage, mood instability,agitation, mental confusion, throat petechiae, nosebleeds, bloody urine,vomiting, black stools, swollen and/or painful liver, disseminatedintravascular coagulation, acute kidney failure, shock and acuterespiratory distress syndrome. In some embodiments, a compound ofFormula (I), or a pharmaceutical acceptable salt thereof, can ameliorateone or more symptoms of CCHF.

California encephalitis virus is another virus of the Bunyaviridaefamily, and is a member of the Orthobunavirus genus. Symptoms of aCalifornia encephalitis virus infection include, but are not limited tofever, chills, nausea, vomiting, headache, abdominal pain, lethargy,focal neurologic findings, focal motor abnormalities, paralysis,drowsiness, lack of mental alertness and orientation and seizures. Insome embodiments, a compound of Formula (I), or a pharmaceuticalacceptable salt thereof, can ameliorate, treat, and/or inhibitreplication of California encephalitis virus. In some embodiments, acompound of Formula (I), or a pharmaceutical acceptable salt thereof,can ameliorate one or more symptoms of a California encephalitis viralinfection.

Viruses within the Hantavirus genus can cause hantavirus hemorrhagicfever with renal syndrome (HFRS) (caused by viruses such as HantaanRiver virus, Dobrava-Belgrade virus, Saaremaa virus, Seoul virus, andPuumala virus) and hantavirus pulmonary syndrome (HPS). Viruses that cancause HPS include, but are not limited to, Black Creek Canal virus(BCCV), New York virus (NYV), Sin Nombre virus (SNV). In someembodiments, a compound of Formula (I), or a pharmaceutical acceptablesalt thereof, can ameliorate and/or treat HFRS. In some embodiments, acompound of Formula (I), or a pharmaceutical acceptable salt thereof,can ameliorate and/or treat HPS. Clinical symptoms of HFRS includeredness of cheeks and/or nose, fever, chills, sweaty palms, diarrhea,malaise, headaches, nausea, abdominal and back pain, respiratoryproblems, gastro-intestinal problems, tachycardia, hypoxemia, renalfailure, proteinuria and diuresis. Clinical symptoms of HPS includeflu-like symptoms (for example, cough, myalgia, headache, lethargy andshortness-of-breath that can deteriorate into acute respiratoryfailure). In some embodiments, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can ameliorate one or moresymptoms of HFRS. In some embodiments, a compound of Formula (I), or apharmaceutical acceptable salt thereof, can ameliorate one or moresymptoms of HPS.

Various indicators for determining the effectiveness of a method fortreating and/or ameliorating a Coronaviridae, a Togaviridae, aHepeviridae and/or a Bunyaviridae viral infection are known to thoseskilled in the art. Example of suitable indicators include, but are notlimited to, a reduction in viral load, a reduction in viral replication,a reduction in time to seroconversion (virus undetectable in patientserum), a reduction of morbidity or mortality in clinical outcomes,and/or other indicator(s) of disease response. Further indicatorsinclude one or more overall quality of life health indicators, such asreduced illness duration, reduced illness severity, reduced time toreturn to normal health and normal activity, and reduced time toalleviation of one or more symptoms. In some embodiments, a compound ofFormula (I), or a pharmaceutically acceptable salt thereof, can resultin the reduction, alleviation or positive indication of one or more ofthe aforementioned indicators compared to a subject who is untreatedsubject.

As Hepatitis E can affect the liver, a variety of indicators fordetermining the effectiveness of a compound for treating and/orameliorating a liver condition associated with a HEV infection are knownto those skilled in the art. Examples of suitable indicators include areduction in the rate of liver function decrease; stasis in liverfunction; improvement in liver function; reduction in one or moremarkers of liver dysfunction, including alanine transaminase, aspartatetransaminase, total bilirubin, conjugated bilirubin, gamma glutamyltranspeptidase. Similarly, successful therapy with an effective amountof a compound or a pharmaceutical composition described herein (forexample, a compound of Formula (I), or a pharmaceutically acceptablesalt thereof) can reduce the incidence of liver cancer in HEV infectedsubjects.

In some embodiments, an effective amount of a compound of Formula (I),or a pharmaceutically acceptable salt thereof, can reduce a level of amarker of liver fibrosis by at least about 10%, at least about 20%, atleast about 25%, at least about 30%, at least about 35%, at least about40%, at least about 45%, at least about 50%, at least about 55%, atleast about 60%, at least about 65%, at least about 70%, at least about75%, or at least about 80%, or more, compared to the level of the markerin an untreated subject, or to a placebo-treated subject. Methods ofmeasuring serum markers are known to those skilled in the art andinclude immunological-based methods, e.g., enzyme-linked immunosorbentassays (ELISA), radioimmunoassays, and the like, using antibody specificfor a given serum marker. A non-limiting list of examples of markersincludes measuring the levels of serum alanine aminotransferase (ALT),aspartate aminotransferase (AST), alkaline phosphatase (ALP),gamma-glutamyl transpeptidase (GGT) and total bilirubin (TBIL) usingknown methods. In general, an ALT level of less than about 45 IU/L(international units/liter), an AST in the range of 10-34 IU/L, ALP inthe range of 44-147 IU/L, GGT in the range of 0-51 IU/L, TBIL in therange of 0.3-1.9 mg/dL is considered normal. In some embodiments, aneffective amount of a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can be an amount effective to reduce ALT, AST,ALP, GGT and/or TBIL levels to with what is considered a normal level.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can result in a reduction in the length and/orseverity of one or more symptoms associated with a Coronaviridae, aTogaviridae, a Hepeviridae and/or a Bunyaviridae virus infectioncompared to a subject who is an untreated subject. Table 1 provides someembodiments of the percentage improvements obtained using a compound ofFormula (I), or a pharmaceutically acceptable salt thereof, as comparedto an untreated subject. Examples include the following: in someembodiments, a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, can result in a duration of illness that is in the rangeof about 10% to about 30% less than compared to the duration of illnessexperienced by a subject who is untreated for a Bunyaviridae virusinfection (such as Rift Valley Fever virus); and in some embodiments, acompound of Formula (I), or a pharmaceutically acceptable salt thereof,results in a severity of a symptom (such as one of those describedherein) that is 25% less than compared to the severity of the samesymptom experienced by a subject who is untreated for a VEEV infection.Methods of quantifying the severity of a side effect and/or symptom areknown to those skilled in the art.

TABLE 1 Number of Severity of Duration of Severity of side effects sideeffect(s) illness symptom(s) 10% less 10% less 10% less 10% less 25%less 25% less 25% less 25% less 40% less 40% less 40% less 40% less 50%less 50% less 50% less 50% less 60% less 60% less 60% less 60% less 70%less 70% less 70% less 70% less 80% less 80% less 80% less 80% less 90%less 90% less 90% less 90% less about 10% to about 10% to about 10%about 10% to about 30% about 30% to about about 30% less less 30% lessless about 20% to about 20% to about 20% about 20% to about 50% about50% to about about 50% less less 50% less less about 30% to about 30% toabout 30% about 30% to about 70% about 70% to about about 70% less less70% less less about 20% to about 20% to about 20% about 20% to about 80%about 80% to about about 80% less less 80% less less

In some embodiments, the compound can be a compound of Formula (I), or apharmaceutical acceptable salt thereof, wherein R^(1A) is hydrogen. Inother embodiments, the compound can be a compound of Formula (I),wherein compound of Formula (I) is a mono, di, or triphosphate, or apharmaceutically acceptable salt of the foregoing. In still otherembodiments, the compound can be a compound of Formula (I), whereincompound of Formula (I) is a thiomonophosphate, alpha-thiodiphosphate,or alpha-thiotriphosphate, or a pharmaceutically acceptable salt of theforegoing. In some embodiments, the compound of Formula (I), or apharmaceutical acceptable salt thereof, that can be used to ameliorateand/or treat a Coronaviridae, a Togaviridae, a Hepeviridae and/or aBunyaviridae virus infection and/or inhibit replication of aCoronaviridae virus, a Togaviridae virus, a Hepeviridae virus and/or aBunyaviridae virus can be any of the embodiments provided in any of theembodiments described in paragraphs [0158]-[0218].

As used herein, a “subject” refers to an animal that is the object oftreatment, observation or experiment. “Animal” includes cold- andwarm-blooded vertebrates and invertebrates such as fish, shellfish,reptiles and, in particular, mammals. “Mammal” includes, withoutlimitation, mice, rats, rabbits, guinea pigs, dogs, cats, sheep, goats,cows, horses, primates, such as monkeys, chimpanzees, and apes, and, inparticular, humans. In some embodiments, the subject is human.

As used herein, the terms “treating,” “treatment,” “therapeutic,” or“therapy” do not necessarily mean total cure or abolition of the diseaseor condition. Any alleviation of any undesired signs or symptoms of adisease or condition, to any extent can be considered treatment and/ortherapy. Furthermore, treatment may include acts that may worsen thepatient's overall feeling of well-being or appearance.

The terms “therapeutically effective amount” and “effective amount” areused to indicate an amount of an active compound, or pharmaceuticalagent, that elicits the biological or medicinal response indicated. Forexample, an effective amount of compound can be the amount needed toprevent, alleviate or ameliorate symptoms of disease or prolong thesurvival of the subject being treated This response may occur in atissue, system, animal or human and includes alleviation of the signs orsymptoms of the disease being treated. Determination of an effectiveamount is well within the capability of those skilled in the art, inview of the disclosure provided herein. The effective amount of thecompounds disclosed herein required as a dose will depend on the routeof administration, the type of animal, including human, being treated,and the physical characteristics of the specific animal underconsideration. The dose can be tailored to achieve a desired effect, butwill depend on such factors as weight, diet, concurrent medication andother factors which those skilled in the medical arts will recognize.

As will be readily apparent to one skilled in the art, the useful invivo dosage to be administered and the particular mode of administrationwill vary depending upon the age, weight, the severity of theaffliction, and mammalian species treated, the particular compoundsemployed, and the specific use for which these compounds are employed.The determination of effective dosage levels, that is the dosage levelsnecessary to achieve the desired result, can be accomplished by oneskilled in the art using routine methods, for example, human clinicaltrials and in vitro studies.

The dosage may range broadly, depending upon the desired effects and thetherapeutic indication. Alternatively dosages may be based andcalculated upon the surface area of the patient, as understood by thoseof skill in the art. Although the exact dosage will be determined on adrug-by-drug basis, in most cases, some generalizations regarding thedosage can be made. The daily dosage regimen for an adult human patientmay be, for example, an oral dose of between 0.01 mg and 3000 mg of eachactive ingredient, preferably between 1 mg and 700 mg, e.g. 5 to 200 mg.The dosage may be a single one or a series of two or more given in thecourse of one or more days, as is needed by the subject. In someembodiments, the compounds will be administered for a period ofcontinuous therapy, for example for a week or more, or for months oryears. In some embodiments, a compound of Formula (I), or apharmaceutically acceptable salt thereof, can be administered lessfrequently compared to the frequency of administration of another agent.In some embodiments, the total time of the treatment regime with acompound of Formula (I), or a pharmaceutically acceptable salt thereof,can less compared to the total time of the treatment regime with anotheragent.

In instances where human dosages for compounds have been established forat least some condition, those same dosages may be used, or dosages thatare between about 0.1% and 500%, more preferably between about 25% and250% of the established human dosage. Where no human dosage isestablished, as will be the case for newly-discovered pharmaceuticalcompositions, a suitable human dosage can be inferred from ED₅₀ or ID₅₀values, or other appropriate values derived from in vitro or in vivostudies, as qualified by toxicity studies and efficacy studies inanimals.

In cases of administration of a pharmaceutically acceptable salt,dosages may be calculated as the free base. As will be understood bythose of skill in the art, in certain situations it may be necessary toadminister the compounds disclosed herein in amounts that exceed, oreven far exceed, the above-stated, preferred dosage range in order toeffectively and aggressively treat particularly aggressive diseases orinfections.

Dosage amount and interval may be adjusted individually to provideplasma levels of the active moiety which are sufficient to maintain themodulating effects, or minimal effective concentration (MEC). The MECwill vary for each compound but can be estimated from in vitro data.Dosages necessary to achieve the MEC will depend on individualcharacteristics and route of administration. However, HPLC assays orbioassays can be used to determine plasma concentrations. Dosageintervals can also be determined using MEC value. Compositions should beadministered using a regimen which maintains plasma levels above the MECfor 10-90% of the time, preferably between 30-90% and most preferablybetween 50-90%. In cases of local administration or selective uptake,the effective local concentration of the drug may not be related toplasma concentration.

It should be noted that the attending physician would know how to andwhen to terminate, interrupt, or adjust administration due to toxicityor organ dysfunctions. Conversely, the attending physician would alsoknow to adjust treatment to higher levels if the clinical response werenot adequate (precluding toxicity). The magnitude of an administrateddose in the management of the disorder of interest will vary with theseverity of the condition to be treated and to the route ofadministration. The severity of the condition may, for example, beevaluated, in part, by standard prognostic evaluation methods. Further,the dose and perhaps dose frequency, will also vary according to theage, body weight, and response of the individual patient. A programcomparable to that discussed above may be used in veterinary medicine.

Compounds disclosed herein can be evaluated for efficacy and toxicityusing known methods. For example, the toxicology of a particularcompound, or of a subset of the compounds, sharing certain chemicalmoieties, may be established by determining in vitro toxicity towards acell line, such as a mammalian, and preferably human, cell line. Theresults of such studies are often predictive of toxicity in animals,such as mammals, or more specifically, humans. Alternatively, thetoxicity of particular compounds in an animal model, such as mice, rats,rabbits, or monkeys, may be determined using known methods. The efficacyof a particular compound may be established using several recognizedmethods, such as in vitro methods, animal models, or human clinicaltrials. When selecting a model to determine efficacy, the skilledartisan can be guided by the state of the art to choose an appropriatemodel, dose, route of administration and/or regime.

As described herein, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can have a moiety(ies) that neutralize thecharge of the phosphate or thiophosphate. By neutralizing the charge onthe phosphate or thiophosphate, penetration of the cell membrane may befacilitated as a result of the increased lipophilicity of the compound.Once absorbed and taken inside the cell, the groups attached to thephosphorus can be easily removed by esterases, proteases and/or otherenzymes. In some embodiments, the groups attached to the phosphorus canbe removed by simple hydrolysis. Inside the cell, the phosphate thusreleased may then be metabolized by cellular enzymes to the diphosphateor the active triphosphate. Likewise, the thio-phosphate may bemetabolized to the alpha-thiodiphosphate or the alpha-thiotriphosphate.Furthermore, in some embodiments, varying the substituents on a compounddescribed herein, such as a compound of Formula (I), or apharmaceutically acceptable salt thereof, can help maintain the efficacyof such the compound by reducing undesirable effects, such asisomerization.

In some embodiments, the phosphorylation of a thio-monophosphate of acompound of Formula (I), or a pharmaceutically acceptable salt thereof,can be stereoselective. For example, a thio-monophosphate of a compoundof Formula (I) can be phosphorylated to give an alpha-thiodiphosphateand/or an alpha-thiotriphosphate compound that can be enriched in the(R) or (S) diastereomer with respect to the 5′-O-phosphorous atom. Forexample, one of the (R) and (S) configuration with respect to the5′-O-phosphorous atom of the alpha-thiodiphosphate and/or thealpha-thiotriphosphate compound can be present in an amount >50%, ≧75%,≧90%, ≧95% or ≧99% compared to the amount of the other of the (R) or (S)configuration with respect to the 5′-O-phosphorous atom. In someembodiments, phosphorylation of a compound of Formula (I), or apharmaceutically acceptable salt thereof, can result in the formation ofa compound that has the (R)-configuration at the 5′-O-phosphorous atom.In some embodiments, phosphorylation of a compound of Formula (I), or apharmaceutically acceptable salt thereof, can result in formation of acompound that has the (S)-configuration at the 5′-O-phosphorous atom.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can act as a chain terminator of RNA synthesis.For example, compounds of Formula (I) can contain a moiety at the2′-carbon position such that once the compound is incorporated into anRNA chain, no further elongation is observed to occur.

For example, a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, can contain a non-hydrogen 2′-carbon modification such asan optionally substituted C₁₋₆ alkyl, an optionally substituted C₂₋₆alkenyl or an optionally substituted C₂₋₆ alkynyl.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can have increased metabolic and/or plasmastability. In some embodiments, a compound of Formula (I), or apharmaceutically acceptable salt thereof, can be more resistant tohydrolysis and/or more resistant to enzymatic transformations. Forexample, a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, can have increased metabolic stability, increased plasmastability, can be more resistant to hydrolysis and/or can be moreresistant to enzymatic transformations compared to a compound that isidentical in structure but for having O¹ as OH, R^(A), R^(2A), R^(5A),R^(a1) and R^(a2) are each hydrogen and R^(3A) and R^(4A) are each OH.In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can have improved properties. A non-limitinglist of example properties include, but are not limited to, increasedbiological half-life, increased bioavailability, increase potency, asustained in vivo response, increased dosing intervals, decreased dosingamounts, decreased cytotoxicity, reduction in required amounts fortreating disease conditions, reduction in viral load, reduction in timeto seroconversion (i.e., the virus becomes undetectable in patientserum), increased sustained viral response, a reduction of morbidity ormortality in clinical outcomes, increased subject compliance, decreasedliver conditions (such as liver fibrosis, liver cirrhosis and/or livercancer), and compatibility with other medications. In some embodiments,a compound of Formula (I), or a pharmaceutically acceptable saltthereof, can have a biological half-life of greater than 24 hours. Insome embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can have a biological half-life greater than acompound that is identical in structure but for having O¹ as OH, R^(A),R^(2A), R^(5A), R^(a1) and R^(a2) are each hydrogen and R^(3A) andR^(4A) are each OH. In some embodiments, a compound of Formula (I), or apharmaceutically acceptable salt thereof, can have more potent antiviralactivity compared to a compound that is identical in structure but forhaving O¹ as OH, R^(A), R^(2A), R^(5A), R^(a1) and R^(a2) are eachhydrogen and R^(3A) and R^(4A) are each OH.

Additionally, in some embodiments, the presence of a moiety(ies) thatneutralizes the charge of the phosphate or thiophosphate can increasethe stability of the compound by inhibiting its degradation. Also, insome embodiments, the presence of a moiety(ies) that neutralizes thecharge of the phosphate or thiophosphate can make the compound moreresistant to cleavage in vivo and provide sustained, extended efficacy.In some embodiments, a moiety(ies) that neutralizes the charge of thephosphate or thiophosphate can facilitate the penetration of the cellmembrane by a compound of Formula (I) by making the compound morelipophilic. In some embodiments, a moiety(ies) that neutralizes thecharge of the phosphate or thiophosphate can have improved oralbioavailability, improved aqueous stability and/or reduced risk ofbyproduct-related toxicity. In some embodiments, for comparisonpurposes, a compound of Formula (I) can be compared to a compound thatis identical in structure but for having O¹ as OH, R^(A), R^(2A),R^(5A), R^(a1) and R^(a2) are each hydrogen and R^(3A) and R^(4A) areeach OH.

Combination Therapies

In some embodiments, the compounds disclosed herein, such as a compoundof Formula (I), or a pharmaceutically acceptable salt thereof, or apharmaceutical composition that includes a compound described herein, ora pharmaceutically acceptable salt thereof, can be used in combinationwith one or more additional agent(s) for treating, ameliorating and/orinhibiting a Coronaviridae, a Togaviridae, a Hepeviridae and/or aBunyaviridae viral infection.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can be administered with one or more additionalagent(s) together in a single pharmaceutical composition. In someembodiments, a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, can be administered with one or more additional agent(s)as two or more separate pharmaceutical compositions. For example, acompound of Formula (I), or a pharmaceutically acceptable salt thereof,can be administered in one pharmaceutical composition, and at least oneof the additional agents can be administered in a second pharmaceuticalcomposition. If there are at least two additional agents, one or more ofthe additional agents can be in a first pharmaceutical composition thatincludes a compound of Formula (I), or a pharmaceutically acceptablesalt thereof, and at least one of the other additional agent(s) can bein a second pharmaceutical composition.

The dosing amount(s) and dosing schedule(s) when using a compound ofFormula (I), or a pharmaceutically acceptable salt thereof, or apharmaceutical composition that includes a compound of Formula (I), or apharmaceutically acceptable salt thereof, and one or more additionalagents are within the knowledge of those skilled in the art. The orderof administration of a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, with one or more additional agent(s) can vary.In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can be administered prior to all additionalagents. In other embodiments, a compound of Formula (I), or apharmaceutically acceptable salt thereof, can be administered prior toat least one additional agent. In still other embodiments, a compound ofFormula (I), or a pharmaceutically acceptable salt thereof, can beadministered concomitantly with one or more additional agent(s). In yetstill other embodiments a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, can be administered subsequent to theadministration of at least one additional agent. In some embodiments, acompound of Formula (I), or a pharmaceutically acceptable salt thereof,can be administered subsequent to the administration of all additionalagents.

In some embodiments, the combination of a compound of Formula (I), or apharmaceutically acceptable salt thereof, in combination with one ormore additional agent(s) can result in an additive effect. In someembodiments, the combination of a compound of Formula (I), or apharmaceutically acceptable salt thereof, used in combination with oneor more additional agent(s) can result in a synergistic effect. In someembodiments, the combination of a compound of Formula (I), or apharmaceutically acceptable salt thereof, used in combination with oneor more additional agent(s) can result in a strongly synergistic effect.In some embodiments, the combination of a compound of Formula (I), or apharmaceutically acceptable salt thereof, in combination with one ormore additional agent(s) is not antagonistic.

As used herein, the term “antagonistic” means that the activity of thecombination of compounds is less compared to the sum of the activitiesof the compounds in combination when the activity of each compound isdetermined individually (i.e. as a single compound). As used herein, theterm “synergistic effect” means that the activity of the combination ofcompounds is greater than the sum of the individual activities of thecompounds in the combination when the activity of each compound isdetermined individually. As used herein, the term “additive effect”means that the activity of the combination of compounds is about equalto the sum of the individual activities of the compound in thecombination when the activity of each compound is determinedindividually.

A potential advantage of utilizing a compound of Formula (I), or apharmaceutically acceptable salt thereof, in combination with one ormore additional agent(s) may be a reduction in the required amount(s) ofone or more additional agent(s) that is effective in treating a diseasecondition disclosed herein (for example, a Coronaviridae, a Togaviridae,a Hepeviridae and/or a Bunyaviridae virus infection), as compared to theamount required to achieve same therapeutic result when one or moreadditional agent(s) are administered without a compound of Formula (I),or a pharmaceutically acceptable salt thereof. For example, for treatingMERS-CoV, the amount of the additional agent (including apharmaceutically acceptable salt thereof) used in combination can beless compared to the amount of the additional agent (including apharmaceutically acceptable salt thereof) needed to achieve the sameviral load reduction when administered as a monotherapy. Anotherpotential advantage of utilizing a compound of Formula (I), or apharmaceutically acceptable salt thereof, in combination with one ormore additional agent(s) is that the use of two or more compounds havingdifferent mechanism of actions can create a higher barrier to thedevelopment of resistant viral strains compared to the barrier when acompound is administered as monotherapy.

Additional advantages of utilizing a compound of Formula (I), or apharmaceutically acceptable salt thereof, in combination with one ormore additional agent(s) may include little to no cross resistancebetween a compound of Formula (I), or a pharmaceutically acceptable saltthereof, and one or more additional agent(s) thereof; different routesfor elimination of a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, and one or more additional agent(s); little tono overlapping toxicities between a compound of Formula (I), or apharmaceutically acceptable salt thereof, and one or more additionalagent(s); little to no significant effects on cytochrome P450; little tono pharmacokinetic interactions between a compound of Formula (I), or apharmaceutically acceptable salt thereof, and one or more additionalagent(s); greater percentage of subjects achieving a sustained viralresponse compared to when a compound is administered as monotherapyand/or a decrease in treatment time to achieve a sustained viralresponse compared to when a compound is administered as monotherapy.

For treating of a Coronaviridae, a Togaviridae, a Hepeviridae and/or aBunyaviridae virus infection, examples of additional agents that can beused in combination with a compound of Formula (I), or apharmaceutically acceptable salt thereof, or a pharmaceuticalcomposition that includes a compound of Formula (I), or apharmaceutically acceptable salt thereof, are described herein. Anexample of a compound that can be used in combination with a compounddescribed herein (for example, a compound of Formula (I), or apharmaceutically acceptable salt thereof, or a pharmaceuticalcomposition that includes a compound of Formula (I), or apharmaceutically acceptable salt thereof) for treating a coronavirus(such as MERS-CoV) is K22((Z)—N-(3-(4-(4-bromophenyl)-4-hydroxypiperidin-1-yl)-3-oxo-1-phenylprop-1-en-2-yl)benzamide).Compounds that can be used in combination for the treatment of MERS-CoVinclude an interferon (for example, interferon-alpha 2b and/or IFNβtreatment), ribavirin and SB203580 (InvivoGen,4-(4′-Fluorophenyl)-2-(4′-methylsulfinylphenyl)-5-(4′-pyridyl)-imidazole).A candidate for treating CHIKV that can be used in combination isChloroquine.

Compounds

Some embodiments disclosed herein relate to a method and/or use of acompound of Formula (I), or a pharmaceutically acceptable salt thereof:

wherein: B^(1A) can be an optionally substituted heterocyclic base or anoptionally substituted heterocyclic base with a protected amino group;-------- can be absent or a single bond, provided that both -------- areabsent or both -------- are a single bond; when -------- are bothabsent, then Z¹ can be absent, O¹ can be OR^(1A), R^(3A) can be selectedfrom hydrogen, halo, OH, —OC(═O)R″^(A) and an optionally substitutedO-linked amino acid, R^(4A) can be selected from hydrogen, OH, halo, N₃,—OC(═O)R″^(B), an optionally substituted O-linked amino acid andNR″^(B1)R″^(B2), or R^(3A) and R^(4A) can be both an oxygen atomconnected via a carbonyl to form a 5-membered ring; when -------- areeach a single bond, then Z¹ can be

O¹ can be O, R^(3A) can be O; R^(4A) can be selected from hydrogen, OH,halo, N₃, —OC(═O)R″^(B), an optionally substituted O-linked amino acidand NR″^(B1)R″^(B2); and R^(1B) can be selected from O⁻, OH, an—O-optionally substituted C₁₋₆ alkyl.

an optionally substituted N-linked amino acid and an optionallysubstituted N-linked amino acid ester derivative; R^(a1) and R^(a2) canbe independently hydrogen or deuterium; R^(A) can be hydrogen,deuterium, an unsubstituted C₁₋₃ alkyl, an unsubstituted C₂₋₄ alkenyl,an unsubstituted C₂₋₃ alkynyl or cyano; R^(1A) can be selected fromhydrogen, an optionally substituted acyl, an optionally substitutedO-linked amino acid,

R^(2A) can be hydrogen, halo, an unsubstituted C₁₋₄ alkyl, anunsubstituted C₂₋₄ alkenyl, an unsubstituted C₂₋₄ alkynyl, —CHF₂, CF₃,—(CH₂)₁₋₆ halogen, —(CH₂)₁₋₆N₃, —(CH₂)₁₋₆NH₂ or —CN; R^(5A) can beselected from hydrogen, halo, OH, an optionally substituted C₁₋₆ alkyl,an optionally substituted C₂₋₆ alkenyl and an optionally substitutedC₂₋₆ alkynyl; R^(6A), R^(7A) and R^(8A) can be independently selectedfrom absent, hydrogen, an optionally substituted C₁₋₂₄ alkyl, anoptionally substituted C₂₋₂₄ alkenyl, an optionally substituted C₂₋₂₄alkynyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted C₃₋₆ cycloalkenyl, an optionally substituted aryl, anoptionally substituted heteroaryl, an optionally substituted aryl(C₁₋₆alkyl), an optionally substituted *—(CR^(15A)R^(16A))_(p)—O—C₁₋₂₄ alkyl,an optionally substituted *—(CR^(17A)R^(18A))_(q)—O—C₁₋₂₄ alkenyl,

or R^(6A) can be

and R^(7A) can be absent or hydrogen; or R^(6A) and R^(7A) can be takentogether to form a moiety selected from an optionally substituted

and an optionally substituted

wherein the oxygens connected to R^(6A) and R^(7A), the phosphorus andthe moiety form a six-membered to ten-membered ring system; R^(9A) canbe independently selected from an optionally substituted C₁₋₂₄ alkyl, anoptionally substituted C₂₋₂₄ alkenyl, an optionally substituted C₂₋₂₄alkynyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted C₃₋₆ cycloalkenyl, NR^(30A)R^(31A), an optionallysubstituted N-linked amino acid and an optionally substituted N-linkedamino acid ester derivative; R^(10A) and R^(11A) can be independently anoptionally substituted N-linked amino acid or an optionally substitutedN-linked amino acid ester derivative; R^(12A) and R^(13A) can beindependently absent or hydrogen; R^(14A) can be O⁻, OH or methyl; eachR^(15A), each R^(16A), each R^(17A) and each R^(18A) can beindependently hydrogen, an optionally substituted C₁₋₂₄ alkyl or analkoxy; R^(19A), R^(20A), R^(22A), R^(23A), R^(2B), R^(3B), R^(5B) andR^(6B) can be independently selected from hydrogen, an optionallysubstituted C₁₋₂₄ alkyl and an optionally substituted aryl; R^(21A) andR^(4B) can be independently selected from hydrogen, an optionallysubstituted C₁₋₂₄ alkyl, an optionally substituted aryl, an optionallysubstituted —O—C₁₋₂₄ alkyl, an optionally substituted —O-aryl, anoptionally substituted —O-heteroaryl and an optionally substituted—O-monocyclic heterocyclyl; R^(24A) and R^(7B) can be independentlyselected from of hydrogen, an optionally substituted C₁₋₂₄ alkyl, anoptionally substituted aryl, an optionally substituted —O—C₁₋₂₄ alkyl,an optionally substituted —O-aryl, an optionally substituted—O-heteroaryl, an optionally substituted —O-monocyclic heterocyclyl and

R^(25A), R^(26A), R^(29A), R^(8B) and R^(9B) can be independentlyselected from hydrogen, an optionally substituted C₁₋₂₄ alkyl and anoptionally substituted aryl; R^(27A1) and R^(27A2) can be independentlyselected from —C≡N, an optionally substituted C₂₋₈ organylcarbonyl, anoptionally substituted C₂₋₈ alkoxycarbonyl and an optionally substitutedC₂₋₈ organylaminocarbonyl; R^(28A) can be selected from hydrogen, anoptionally substituted C₁₋₂₄ alkyl, an optionally substituted C₂₋₂₄alkenyl, an optionally substituted C₂₋₂₄ alkynyl, an optionallysubstituted C₃₋₆ cycloalkyl and an optionally substituted C₃₋₆cycloalkenyl; R^(30A) and R^(31A) can be independently selected fromhydrogen, an optionally substituted C₁₋₂₄ alkyl, an optionallysubstituted C₂₋₂₄ alkenyl, an optionally substituted C₂₋₂₄ alkynyl, anoptionally substituted C₃₋₆ cycloalkyl, an optionally substituted C₃₋₆cycloalkenyl and an optionally substituted aryl(C₁₋₄ alkyl); R″^(A) andeach R″^(B) can be independently an optionally substituted C₁₋₂₄ alkyl;each R″^(B1) and each R″^(B2) can be independently hydrogen or anoptionally substituted C₁₋₆ alkyl; m and w can be independently 0 or 1;p and q can be independently 1, 2 or 3; r and s can be independently 0,1, 2 or 3; t and v can be independently or 2; u and y can beindependently 3, 4 or 5; and Z^(1A), Z^(2A), Z^(3A), Z^(4A), Z^(1B) andZ^(2B) can be independently oxygen (O) or sulfur (S).

A compound of Formula (I) can be a nucleoside, a nucleotide (including amonophosphate, a diphosphate, a triphosphate, thiomonophosphate,alpha-thiodiphosphate and/or alpha-thiotriphosphate) or a nucleotideprodrug. In some embodiments, -------- can be both absent, Z¹ can beabsent, O¹ can be OR^(1A), R^(3A) can be selected from hydrogen, halo,OH, —OC(═O)R″^(A) and an optionally substituted O-linked amino acid,R^(4A) can be selected from OH, halo, —OC(═O)R″^(B) and an optionallysubstituted O-linked amino acid, or R^(3A) and R^(4A) can be both anoxygen atom connected via a carbonyl to form a 5-membered ring.

Various substituents can be attached to the 5′-position of Formula (I)when both -------- are absent. In some embodiments, R^(1A) can behydrogen. In other embodiments, R^(1A) can be an optionally substitutedacyl. For example, R^(1A) can be —C(═O)R^(39A), wherein R^(39A) can beselected from an optionally substituted C₁₋₁₂ alkyl, an optionallysubstituted C₂₋₁₂ alkenyl, an optionally substituted C₂₋₁₂ alkynyl, anoptionally substituted C₃₋₈ cycloalkyl, an optionally substituted C₅₋₈cycloalkenyl, an optionally substituted C₆₋₁₀ aryl, an optionallysubstituted heteroaryl, an optionally substituted heterocyclyl, anoptionally substituted aryl(C₁₋₆ alkyl), an optionally substitutedheteroaryl(C₁₋₆ alkyl) and an optionally substituted heterocyclyl(C₁₋₆alkyl). In some embodiments, R^(39A) can be a substituted C₁₋₁₂ alkyl.In other embodiments, R^(39A) can be an unsubstituted C₁₋₁₂ alkyl. Insome embodiments, R^(1A) can be —C(═O)-unsubstituted C₁₋₄ alkyl. In someembodiments, both R^(a1) and R^(a2) can be hydrogen. In otherembodiments, R^(a1) can be hydrogen and R^(a2) can be deuterium. Instill other embodiments, both R^(a1) and R^(a2) can be deuterium.

In still other embodiments, R^(1A) can be an optionally substitutedO-linked amino acid. Examples of suitable O-linked amino acids includealanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine,proline, serine, tyrosine, arginine, histidine, isoleucine, leucine,lysine, methionine, phenylalanine, threonine, tryptophan and valine.Additional examples of suitable amino acids include, but are not limitedto, ornithine, hypusine, 2-aminoisobutyric acid, dehydroalanine,gamma-aminobutyric acid, citrulline, beta-alanine, alpha-ethyl-glycine,alpha-propyl-glycine and norleucine. In some embodiments, the O-linkedamino acid can have the structure

wherein R^(40A) can be selected from hydrogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₁₋₆ haloalkyl, an optionallysubstituted C₃₋₆ cycloalkyl, an optionally substituted C₆ aryl, anoptionally substituted C₁₀ aryl and an optionally substituted aryl(C₁₋₆alkyl); and R^(41A) can be hydrogen or an optionally substituted C₁₋₄alkyl; or R^(40A) and R^(41A) can be taken together to form anoptionally substituted C₃₋₆ cycloalkyl. Those skilled in the artunderstand that when R^(1A) is an optionally substituted O-linked aminoacid, the oxygen of R^(1A)O— of Formula (I) is part of the optionallysubstituted O-linked amino acid. For example, when R^(1A) is

the oxygen indicated with “*” is the oxygen of R^(1A)O— of Formula (I).

When R^(40A) is substituted, R^(40A) can be substituted with one or moresubstituents selected from N-amido, mercapto, alkylthio, an optionallysubstituted aryl, hydroxy, an optionally substituted heteroaryl,O-carboxy and amino. In some embodiments, R^(40A) can be anunsubstituted C₁₋₆ alkyl, such as those described herein. In someembodiments, R^(40A) can be hydrogen. In other embodiments, R^(40A) canbe methyl. In some embodiments, R^(41A) can be hydrogen. In otherembodiments, R^(41A) can be an optionally substituted C₁₋₄ alkyl, suchas methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl.In some embodiments, R^(41A) can be methyl. Depending on the groups thatare selected for R^(40A) and R^(41A), the carbon to which R^(40A) andR^(41A) are attached may be a chiral center. In some embodiment, thecarbon to which R^(40A) and R^(41A) are attached may be a (R)-chiralcenter. In other embodiments, the carbon to which R^(40A) and R^(41A)are attached may be a (S)-chiral center.

Examples of suitable

include the following:

In some embodiments, R^(1A) can be

In some embodiments, R^(6A) and R^(7A) can be both hydrogen. In otherembodiments, R^(6A) and R^(7A) can be both absent. In still otherembodiments, at least one R^(6A) and R^(7A) can be absent. In yet stillother embodiments, at least one R^(6A) and R^(7A) can be hydrogen. Thoseskilled in the art understand that when R^(6A) and/or R^(7A) are absent,the associated oxygen(s) will have a negative charge. For example, whenR^(6A) is absent, the oxygen associated with R^(6A) will have a negativecharge. In some embodiments, Z^(1A) can be O (oxygen). In otherembodiments, Z^(1A) can be S (sulfur). In some embodiments, R^(1A) canbe a monophosphate. In other embodiments, R^(1A) can be amonothiophosphate.

In some embodiments, R^(1A) can be

R^(6A) can be

R^(7A) can be absent or hydrogen; R^(12A) and R^(13A) can beindependently absent or hydrogen; R^(14A) can be O⁻, OH or methyl; and mcan be 0 or 1. In some embodiments, m can be 0, and R^(7A), R^(12A) andR^(13A) can be independently absent or hydrogen. In other embodiments, mcan be 1, and R^(7A), R^(12A) and R^(13A) can be independently absent orhydrogen; and R^(14A) can be O⁻, OH or methyl. In some embodiments, mcan be 1, and R^(7A), R^(12A) and R^(13A) can be independently absent orhydrogen; and R^(14A) can be O⁻ or OH. In other embodiments, m can be 1,and R^(7A), R^(12A) and R^(13A) can be independently absent or hydrogen;and R^(14A) can be methyl. Those skilled in the art understand that whenm is 0, R^(6A) can be a diphosphate, when Z^(1A) is oxygen, or analpha-thiodiphosphate, when Z^(1A) is sulfur. Likewise, those skilled inthe art understand that when m is 1, R^(6A) can be a triphosphate, whenZ^(1A) is oxygen, or an alpha-thiotriphosphate, when Z^(1A) is sulfur.

In some embodiments, when R^(1A) is

one of R^(6A) and R^(7A) can be hydrogen, and the other of R^(6A) andR^(7A) can be selected from an optionally substituted C₁₋₂₄ alkyl, anoptionally substituted C₂₋₂₄ alkenyl, an optionally substituted C₂₋₂₄alkynyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted C₃₋₆ cycloalkenyl, an optionally substituted aryl, anoptionally substituted heteroaryl and an optionally substitutedaryl(C₁₋₆ alkyl). In some embodiments, one of R^(6A) and R^(7A) can behydrogen, and the other of R^(6A) and R^(7A) can be an optionallysubstituted C₁₋₂₄ alkyl. In other embodiments, both R^(6A) and R^(7A)can be independently selected from an optionally substituted C₁₋₂₄alkyl, an optionally substituted C₂₋₂₄ alkenyl, an optionallysubstituted C₂₋₂₄ alkynyl, an optionally substituted C₃₋₆ cycloalkyl, anoptionally substituted C₃₋₆ cycloalkenyl, an optionally substitutedaryl, an optionally substituted heteroaryl and an optionally substitutedaryl(C₁₋₆ alkyl). In some embodiments, both R^(6A) and R^(7A) can be anoptionally substituted C₁₋₂₄ alkyl. In other embodiments, both R^(6A)and R^(7A) can be an optionally substituted C₂₋₂₄ alkenyl. In someembodiments, R^(6A) and R^(7A) can be independently an optionallysubstituted group selected from the following: myristoleyl, myristyl,palmitoleyl, palmityl, sapienyl, oleyl, elaidyl, vaccenyl, linoleyl,α-linolenyl, arachidonyl, eicosapentaenyl, erucyl, docosahexaenyl,caprylyl, capryl, lauryl, stearyl, arachidyl, behenyl, lignoceryl andcerotyl.

In some embodiments, at least one of R^(6A) and R^(7A) can be*—(CR^(15A)R^(16A))_(p)—O—C₁₋₂₄ alkyl. In other embodiments, R^(6A) andR^(7A) can be both *—(CR^(15A)R^(16A))_(p)—O—C₁₋₂₄ alkyl. In someembodiments, each R^(15A) and each R^(16A) can be hydrogen. In otherembodiments, at least one of R^(15A) and R^(16A) can be an optionallysubstituted C₁₋₂₄ alkyl. In other embodiments, at least one of R^(15A)and R^(16A) can be an alkoxy (for example, benzoxy). In someembodiments, p can be 1. In other embodiments, p can be 2. In stillother embodiments, p can be 3.

In some embodiments, at least one of R^(6A) and R^(7A) can be*—(CR^(17A)R^(18A))_(q)—O—C₂₋₂₄ alkenyl. In other embodiments, R^(6A)and R^(7A) can be both *—(CR^(17A)R^(18A))_(q)—O—C₂₋₂₄ alkenyl. In someembodiments, each R^(17A) and each R^(18A) can be hydrogen. In otherembodiments, at least one of R^(17A) and R^(18A) can be an optionallysubstituted C₁₋₂₄ alkyl. In some embodiments, q can be 1. In otherembodiments, q can be 2. In still other embodiments, q can be 3. When atleast one of R^(6A) and R^(7A) is *—(CR^(15A)R^(16A))_(p)—O—C₁₋₂₄ alkylor *—(CR^(17A)R^(18A))_(q)—O—C₂₋₂₄ alkenyl, the C₁₋₂₄ alkyl can beselected from caprylyl, capryl, lauryl, myristyl, palmityl, stearyl,arachidyl, behenyl, lignoceryl, and cerotyl, and the C₂₋₂₄ alkenyl canbe selected from myristoleyl, palmitoleyl, sapienyl, oleyl, elaidyl,vaccenyl, linoleyl, α-linolenyl, arachidonyl, eicosapentaenyl, erucyland docosahexaenyl.

In some embodiments, when R^(1A) is

at least one of R^(6A) and R^(7A) can be selected from

and the other of R^(6A) and R^(7A) can be selected from absent,hydrogen, an optionally substituted C₁₋₂₄ alkyl, an optionallysubstituted C₂₋₂₄ alkenyl, an optionally substituted C₂₋₂₄ alkynyl, anoptionally substituted C₃₋₆ cycloalkyl, an optionally substituted C₃₋₆cycloalkenyl, an optionally substituted aryl, an optionally substitutedheteroaryl and an optionally substituted aryl(C₁₋₆ alkyl).

In some embodiments, at least one of R^(6A) and R^(7A) can be

In some embodiments, both R^(6A) and R^(7A) can be

When one or both of R^(6A) and R^(7A) are

R^(19A) and R^(20A) can be independently selected from hydrogen, anoptionally substituted C₁₋₂₄ alkyl and an optionally substituted aryl;and R^(21A) can be selected from hydrogen, an optionally substitutedC₁₋₂₄ alkyl, an optionally substituted aryl, an optionally substituted—O—C₁₋₂₄ alkyl, an optionally substituted —O-aryl, an optionallysubstituted —O-heteroaryl and an optionally substituted —O-monocyclicheterocyclyl. In some embodiments, R^(19A) and R^(20A) can be hydrogen.In other embodiments, at least one of R^(19A) and R^(20A) can be anoptionally substituted C₁₋₂₄ alkyl or an optionally substituted aryl. Insome embodiments, R^(21A) can be an optionally substituted C₁₋₂₄ alkyl.In some embodiments, R^(21A) can be an unsubstituted C₁₋₄ alkyl. Inother embodiments, R^(21A) can be an optionally substituted aryl. Instill other embodiments, R^(21A) can be an optionally substituted—O—C₁₋₂₄ alkyl, an optionally substituted —O-aryl, an optionallysubstituted —O-heteroaryl or an optionally substituted —O-monocyclicheterocyclyl. In some embodiments, R^(21A) can be an unsubstituted—O—C₁₋₄ alkyl.

In some embodiments, both R^(6A) and R^(7A) can be

When one or both of R^(6A) and R^(7A) are

R^(22A) and R^(23A) can be independently selected from hydrogen, anoptionally substituted C₁₋₂₄ alkyl and an optionally substituted aryl;R^(24A) can be independently selected from hydrogen, an optionallysubstituted C₁₋₂₄ alkyl, an optionally substituted aryl, an optionallysubstituted —O—C₁₋₂₄ alkyl, an optionally substituted —O-aryl, anoptionally substituted —O-heteroaryl and an optionally substituted—O-monocyclic heterocyclyl; s can be 0, 1, 2 or 3; and Z^(4A) can beindependently O (oxygen) or S (sulfur). In some embodiments, R^(22A) andR^(23A) can be hydrogen. In other embodiments, at least one of R^(22A)and R^(23A) can be an optionally substituted C₁₋₂₄ alkyl or anoptionally substituted aryl. In some embodiments, R^(24A) can be anoptionally substituted C₁₋₂₄ alkyl. In some embodiments, R^(24A) can bean unsubstituted C₁₋₄ alkyl. In other embodiments, R^(24A) can be anoptionally substituted aryl. In still other embodiments, R^(24A) can bean optionally substituted —O—C₁₋₂₄ alkyl, an optionally substituted—O-aryl, an optionally substituted —O-heteroaryl or an optionallysubstituted —O-monocyclic heterocyclyl. In yet still other embodiments,R^(24A) can be

In some embodiments, R^(24A) can be an unsubstituted —O—C₁₋₄ alkyl. Insome embodiments, Z^(4A) can be O (oxygen). In other embodiments, Z^(4A)can be or S (sulfur). In some embodiments, s can be 0. In otherembodiments, s can be 1. In still other embodiments, s can be 2. In yetstill other embodiments, s can be 3. In some embodiments, s can be 0 andR^(24A) can be

In some embodiments, one or both of R^(6A) and R^(7A) can be anoptionally substituted isopropyloxycarbonyloxymethyl (POC). In someembodiments, R^(6A) and R^(7A) each can be an optionally substitutedisopropyloxycarbonyloxymethyl (POC) group, and form an optionallysubstituted bis(isopropyloxycarbonyloxymethyl) (bis(POC)) prodrug. Inother embodiments, one or both of R^(6A) and R^(7A) can be an optionallysubstituted pivaloyloxymethyl (POM). In some embodiments, R^(6A) andR^(7A) each can be an optionally substituted pivaloyloxymethyl (POM)group, and form an optionally substituted bis(pivaloyloxymethyl)(bis(POM)) prodrug.

In some embodiments, both R^(6A) and R^(7A) can be

When one or both of R^(6A) and R^(7A) are

R^(27A1) and R^(27A2) can be independently —C≡N or an optionallysubstituted substituent selected from C₂₋₈ organylcarbonyl, C₂₋₈alkoxycarbonyl and C₂₋₈ organylaminocarbonyl; R^(28A) can be selectedfrom hydrogen, an optionally substituted C₁₋₂₄ alkyl, an optionallysubstituted C₂₋₂₄ alkenyl, an optionally substituted C₂₋₂₄ alkynyl, anoptionally substituted C₃₋₆ cycloalkyl and an optionally substitutedC₃₋₆ cycloalkenyl; and t can be 1 or 2. In some embodiments, R^(27A1)can be —C≡N and R^(27A2) can be an optionally substituted C₂₋₈alkoxycarbonyl, such as —C(═O)OCH₃. In other embodiments, R^(27A1) canbe —C≡N and R^(27A2) can be an optionally substituted C₂₋₈organylaminocarbonyl, for example, —C(═O)NHCH₂CH₃ and—C(═O)NHCH₂CH₂phenyl. In some embodiments, both R^(27A1) and R^(27A2)can be an optionally substituted C₂₋₈ organylcarbonyl, such as—C(═O)CH₃. In some embodiments, both R^(27A1) and R^(27A2) can be anoptionally substituted C₁₋₈ alkoxycarbonyl, for example, —C(═O)OCH₂CH₃and —C(═O)OCH₃. In some embodiments, including those described in thisparagraph, R^(28A) can be an optionally substituted C₁₋₄ alkyl. In someembodiment, R^(28A) can be methyl or tert-butyl. In some embodiments, tcan be 1. In other embodiments, t can be 2.

In some embodiments, R^(6A) and R^(7A) can be both an optionallysubstituted aryl. In some embodiments, at least one of R^(6A) and R^(7A)can be an optionally substituted aryl. For example, both R^(6A) andR^(7A) can be an optionally substituted phenyl or an optionallysubstituted naphthyl. When substituted, the substituted aryl can besubstituted with 1, 2, 3 or more than 3 substituents. When more the twosubstituents are present, the substituents can be the same or different.In some embodiments, when at least one of R^(6A) and R^(7A) is asubstituted phenyl, the substituted phenyl can be a para-, ortho- ormeta-substituted phenyl.

In some embodiments, R^(6A) and R^(7A) can be both an optionallysubstituted aryl(C₁₋₆ alkyl). In some embodiments, at least one ofR^(6A) and R^(7A) can be an optionally substituted aryl(C₁₋₆ alkyl). Forexample, both R^(6A) and R^(7A) can be an optionally substituted benzyl.When substituted, the substituted benzyl group can be substituted with1, 2, 3 or more than 3 substituents. When more the two substituents arepresent, the substituents can be the same or different. In someembodiments, the aryl group of the aryl(C₁₋₆ alkyl) can be a para-,ortho- or meta-substituted phenyl.

In some embodiments, R^(6A) and R^(7A) can be both

In some embodiments, at least one of R^(6A) and R^(7A) can be

In some embodiments, R^(25A) can be hydrogen. In other embodiments,R^(25A) can be an optionally substituted C₁₋₂₄ alkyl. In still otherembodiments, R^(25A) can be an optionally substituted aryl (for example,an optionally substituted phenyl). In some embodiments, R^(25A) can be aC₁₋₆ alkyl, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl,isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl(branched and straight-chained). In some embodiments, w can be 0. Inother embodiments, w can be 1. In some embodiments, R^(6A) and R^(7A)can be both an optionally substituted S-acylthioethyl (SATE) group andform an optionally substituted SATE ester prodrug.

In some embodiments, R^(6A) and R^(7A) can be both

In some embodiments, at least one of R^(6A) and R^(7A) can be

In some embodiments, R^(26A) can be hydrogen. In other embodiments,R^(26A) can be an optionally substituted C₁₋₂₄ alkyl. In still otherembodiments, R^(26A) can be an optionally substituted aryl, for example,an optionally substituted phenyl. In some embodiments, R^(26A) can be anoptionally substituted C₁₋₆ alkyl. In some embodiments, R^(26A) can bean unsubstituted C₁₋₆ alkyl. In some embodiments, y can be 3. In otherembodiments, y can be 4. In still other embodiments, y can be 5.

In some embodiments, R^(6A) and R^(7A) can be both

In some embodiments, at least one of R^(6A) and R^(7A) can be

In some embodiments, R^(29A) can be hydrogen. In other embodiments,R^(29A) can be an optionally substituted C₁₋₂₄ alkyl. In someembodiments, R^(29A) can be a C₁₋₄ alkyl, such as methyl, ethyl,n-propyl, iso-propyl, n-butyl, iso-butyl and t-butyl. In still otherembodiments, R^(29A) can be an optionally substituted aryl, such as anoptionally substituted phenyl or an optionally substituted naphthyl. Insome embodiments, R^(6A) and R^(7A) can be both an optionallysubstituted dioxolenone group and form an optionally substituteddioxolenone prodrug.

In some embodiments, R^(6A) and R^(7A) can be taken together to form anoptionally substituted

For example, R^(1A) can be an optionally substituted

When substituted, the ring can be substituted 1, 2, 3 or 3 or moretimes. When substituted with multiple substituents, the substituents canbe the same or different. In some embodiments, when R^(1A) is

the ring can be substituted with an optionally substituted aryl groupand/or an optionally substituted heteroaryl. An example of a suitableheteroaryl is pyridinyl. In some embodiments, R^(6A) and R^(7A) can betaken together to form an optionally substituted

such as

wherein R^(32A) can be an optionally substituted aryl, an optionallysubstituted heteroaryl or an optionally substituted heterocyclyl. Insome embodiments, R^(6A) and R^(7A) can form an optionally substitutedcyclic 1-aryl-1,3-propanyl ester (HepDirect) prodrug moiety.

In some embodiments, R^(6A) and R^(7A) can be taken together to form anoptionally substituted

wherein the oxygens connected to R^(6A) and R^(7A), the phosphorus andthe moiety form a six-membered to ten-membered ring system. Example ofan optionally substituted

include

In some embodiments, R^(6A) and R^(7A) can form an optionallysubstituted cyclosaligenyl (cycloSal) prodrug.

In some embodiments, R^(6A) and R^(7A) can be the same. In someembodiments, R^(6A) and R^(7A) can be different.

In some embodiments, Z^(1A) can be oxygen. In other embodiments, Z^(1A)can be sulfur.

In some embodiments, R^(1A) can be

In some embodiments, R^(8A) can be selected from absent, hydrogen, anoptionally substituted C₁₋₂₄ alkyl, an optionally substituted C₂₋₂₄alkenyl, an optionally substituted C₂₋₂₄ alkynyl, an optionallysubstituted C₃₋₆ cycloalkyl and an optionally substituted C₃₋₆cycloalkenyl; and R^(9A) can be independently selected from anoptionally substituted C₁₋₂₄ alkyl, an optionally substituted C₂₋₂₄alkenyl, an optionally substituted C₂₋₂₄ alkynyl, an optionallysubstituted C₃₋₆ cycloalkyl and an optionally substituted C₃₋₆cycloalkenyl.

In some embodiments, R^(8A) can be hydrogen, and R^(9A) can be anoptionally substituted C₁₋₆ alkyl. Examples of suitable C₁₋₆ alkylsinclude methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,tert-butyl, pentyl (branched and straight-chained), and hexyl (branchedand straight-chained). In other embodiments, R^(8A) can be hydrogen, andR^(9A) can be NR^(30A)R^(31A), wherein R^(30A) and R^(31A) can beindependently selected from hydrogen, an optionally substituted C₁₋₂₄alkyl, an optionally substituted C₂₋₂₄ alkenyl, an optionallysubstituted C₂₋₂₄ alkynyl, an optionally substituted C₃₋₆ cycloalkyl andan optionally substituted C₃₋₆ cycloalkenyl and an optionallysubstituted aryl(C₁₋₄ alkyl). In some embodiments, one of R^(30A) andR^(31A) can be hydrogen and the other of R^(30A) and R^(31A) can be anoptionally substituted C₁₋₆ alkyl, an optionally substituted C₂₋₆alkenyl, an optionally substituted C₂₋₆ alkynyl, an optionallysubstituted C₃₋₆ cycloalkyl, an optionally substituted C₃₋₆ cycloalkenyland an optionally substituted benzyl.

In some embodiments, R^(8A) can be absent or hydrogen; and R^(9A) can bean optionally substituted N-linked amino acid or an optionallysubstituted N-linked amino acid ester derivative. In other embodiments,R^(8A) can be an optionally substituted aryl; and R^(9A) can be anoptionally substituted N-linked amino acid or an optionally substitutedN-linked amino acid ester derivative. In still other embodiments, R^(8A)can be an optionally substituted heteroaryl; and R^(9A) can be anoptionally substituted N-linked amino acid or an optionally substitutedN-linked amino acid ester derivative. In some embodiments, R^(9A) can beselected from alanine, asparagine, aspartate, cysteine, glutamate,glutamine, glycine, proline, serine, tyrosine, arginine, histidine,isoleucine, leucine, lysine, methionine, phenylalanine, threonine,tryptophan, valine and ester derivatives thereof. Examples of anoptionally substituted N-linked amino acid ester derivatives includeoptionally substituted versions of the following: N-alanine isopropylester, N-alanine cyclohexyl ester, N-alanine neopentyl ester, N-valineisopropyl ester and N-leucine isopropyl ester. In some embodiments,R^(9A) can have the structure

wherein R^(33A) can be selected from hydrogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted aryl, an optionally substituted aryl(C₁₋₆ alkyl) and anoptionally substituted haloalkyl; R^(34A) can be selected from hydrogen,an optionally substituted C₁₋₆ alkyl, an optionally substituted C₁₋₆haloalkyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted C₆ aryl, an optionally substituted C₁₀ aryl and anoptionally substituted aryl(C₁₋₆ alkyl); and R^(35A) can be hydrogen oran optionally substituted C₁₋₄ alkyl; or R^(34A) and R^(35A) can betaken together to form an optionally substituted C₃₋₆ cycloalkyl.

When R^(34A) is substituted, R^(34A) can be substituted with one or moresubstituents selected from N-amido, mercapto, alkylthio, an optionallysubstituted aryl, hydroxy, an optionally substituted heteroaryl,O-carboxy and amino. In some embodiments, R^(34A) can be anunsubstituted C₁₋₆ alkyl, such as those described herein. In someembodiments, R^(34A) can be hydrogen. In other embodiments, R^(34A) canbe methyl. In some embodiments, R^(33A) can be an optionally substitutedC₁₋₆ alkyl. Examples of optionally substituted C₁₋₆ alkyls includeoptionally substituted variants of the following: methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched andstraight-chained), and hexyl (branched and straight-chained). In someembodiments, R^(33A) can be methyl or isopropyl. In some embodiments,R^(33A) can be ethyl or neopentyl. In other embodiments, R^(33A) can bean optionally substituted C₃₋₆ cycloalkyl. Examples of optionallysubstituted C₃₋₆ cycloalkyl include optionally substituted variants ofthe following: cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Insome embodiments, R^(33A) can be an optionally substituted cyclohexyl.In still other embodiments, R^(33A) can be an optionally substitutedaryl, such as phenyl and naphthyl. In yet still other embodiments,R^(33A) can be an optionally substituted aryl(C₁₋₆ alkyl). In someembodiments, R^(33A) can be an optionally substituted benzyl. In someembodiments, R^(33A) can be an optionally substituted C₁₋₆ haloalkyl,for example, CF₃. In some embodiments, R^(35A) can be hydrogen. In otherembodiments, R^(35A) can be an optionally substituted C₁₋₄ alkyl, suchas methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl.In some embodiments, R^(35A) can be methyl. In some embodiments, R^(34A)and R^(35A) can be taken together to form an optionally substituted C₃₋₆cycloalkyl. Examples of optionally substituted C₃₋₆ cycloalkyl includeoptionally substituted variants of the following: cyclopropyl,cyclobutyl, cyclopentyl, and cyclohexyl. Depending on the groups thatare selected for R^(34A) and R^(35A), the carbon to which R^(34A) andR^(35A) are attached may be a chiral center. In some embodiment, thecarbon to which R^(34A) and R^(35A) are attached may be a (R)-chiralcenter. In other embodiments, the carbon to which R^(34A) and R^(35A)are attached may be a (S)-chiral center.

In some embodiments, when R^(1A) is

Z^(2A) can be O (oxygen). In other embodiments, when R^(1A) is

Z^(2A) can be S (sulfur). In some embodiments, when R^(1A) is

a compound of Formula (I) can be an optionally substitutedphosphoroamidate prodrug, such as an optionally substituted arylphosphoroamidate prodrug.

In some embodiments, R^(1A) can be

In some embodiments, R^(10A) and R^(11A) can be both an optionallysubstituted N-linked amino acid or an optionally substituted N-linkedamino acid ester derivative. In some embodiments, R^(10A) and R^(11A)can be independently selected from alanine, asparagine, aspartate,cysteine, glutamate, glutamine, glycine, proline, serine, tyrosine,arginine, histidine, isoleucine, leucine, lysine, methionine,phenylalanine, threonine, tryptophan, valine and ester derivativesthereof. In some embodiments, R^(10A) and R^(11A) can be an optionallysubstituted version of the following: N-alanine isopropyl ester,N-alanine cyclohexyl ester, N-alanine neopentyl ester, N-valineisopropyl ester and N-leucine isopropyl ester. In some embodiments,R^(10A) and R^(11A) can independently have the structure

wherein R^(36A) can be selected from hydrogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted aryl, an optionally substituted aryl(C₁₋₆ alkyl) and anoptionally substituted haloalkyl; R^(37A) can be selected from hydrogen,an optionally substituted C₁₋₆ alkyl, an optionally substituted C₁₋₆haloalkyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted C₆ aryl, an optionally substituted C₁₀ aryl and anoptionally substituted aryl(C₁₋₆ alkyl); and R^(38A) can be hydrogen oran optionally substituted C₁₋₄ alkyl; or R^(37A) and R^(38A) can betaken together to form an optionally substituted C₃₋₆ cycloalkyl.

When R^(37A) is substituted, R^(37A) can be substituted with one or moresubstituents selected from N-amido, mercapto, alkylthio, an optionallysubstituted aryl, hydroxy, an optionally substituted heteroaryl,O-carboxy and amino. In some embodiments, R^(37A) can be anunsubstituted C₁₋₆ alkyl, such as those described herein. In someembodiments, R^(37A) can be hydrogen. In other embodiments, R^(37A) canbe methyl. In some embodiments, R^(36A) can be an optionally substitutedC₁₋₆ alkyl. Examples of optionally substituted C₁₋₆ alkyls includeoptionally substituted variants of the following: methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched andstraight-chained), and hexyl (branched and straight-chained). In someembodiments, R^(36A) can be methyl or isopropyl. In some embodiments,R^(36A) can be ethyl or neopentyl. In other embodiments, R^(36A) can bean optionally substituted C₃₋₆ cycloalkyl. Examples of optionallysubstituted C₃₋₆ cycloalkyl include optionally substituted variants ofthe following: cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Insome embodiments, R^(36A) can be an optionally substituted cyclohexyl.In still other embodiments, R^(36A) can be an optionally substitutedaryl, such as phenyl and naphthyl. In yet still other embodiments,R^(36A) can be an optionally substituted aryl(C₁₋₆ alkyl). In someembodiments, R^(36A) can be an optionally substituted benzyl. In someembodiments, R^(36A) can be an optionally substituted C₁₋₆ haloalkyl,for example, CF₃. In some embodiments, R^(38A) can be hydrogen. In otherembodiments, R^(38A) can be an optionally substituted C₁₋₄ alkyl, suchas methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl.In some embodiments, R^(38A) can be methyl. In some embodiments, R^(37A)and R^(38A) can be taken together to form an optionally substituted C₃₋₆cycloalkyl. Examples of optionally substituted C₃₋₆ cycloalkyl includeoptionally substituted variants of the following: cyclopropyl,cyclobutyl, cyclopentyl, and cyclohexyl. Depending on the groups thatare selected for R^(37A) and R^(38A), the carbon to which R^(37A) andR^(38A) are attached may be a chiral center. In some embodiment, thecarbon to which R^(37A) and R^(38A) are attached may be a (R)-chiralcenter. In other embodiments, the carbon to which R^(37A) and R^(38A)are attached may be a (S)-chiral center.

Examples of suitable

groups include the following:

In some embodiments, R^(10A) and R^(11A) can be the same. In someembodiments, R^(10A) and R^(11A) can be different.

In some embodiments, Z^(3A) can be O (oxygen). In other embodiments,Z^(3A) can be S (sulfur). In some embodiments, when R^(1A) is

a compound of Formula (I) can be an optionally substituted phosphonicdiamide prodrug.

Various substituents can be present at the 4′-position of the pentosering. In some embodiments, R^(2A) can be an unsubstituted C₁₋₄ alkyl.Unsubstituted C₁₋₄ alkyls include methyl, ethyl, n-propyl, iso-propyl,n-butyl, iso-butyl and tert-butyl. In other embodiments, R^(2A) can bean unsubstituted C₂₋₄ alkenyl, such as ethenyl, propenyl and butenyl. Instill other embodiments, R^(2A) can be an unsubstituted C₂₋₄ alkynyl,for example, ethynyl, propynyl and butynyl. In yet still otherembodiments, R^(2A) can be a haloalkyl.

Examples of a haloalkyls are —(CH₂)₁₋₆ halogen, —(CH₂)₀₋₅(CH)(halogen)₂and —(CH₂)₀₋₅—C(halogen)₃, —CHF₂ and CF₃. In some embodiments, thehaloalkyl can be —(CH₂)₁₋₆F or —(CH₂)₁₋₆Cl. In some embodiments, thehaloalkyl can be fluoromethyl. In other embodiments, R^(2A) can be—CHF₂. In still other embodiments, R^(2A) can be —CF₃. In yet stillother embodiments, R^(2A) can be a C₁₋₆ azidoalkyl. For example, R^(2A)can be an azidomethyl, azidoethyl, azidopropyl, azidobutyl, azidopentylor azidohexyl. In some embodiments, R^(2A) can be a C₁₋₆ aminoalkyl. Forexample, R^(2A) can be an aminomethyl, aminoethyl, aminopropyl,aminobutyl, aminopentyl or aminohexyl. In other embodiments, R^(2A) canbe halo. For example, R^(2A) can be fluoro (F) or chloro (Cl). In stillother embodiments, R^(2A) can be hydrogen. In yet still otherembodiments, R^(2A) can be —CN.

A variety of substituents can also be present at the 2′-position of thepentose ring. In some embodiments, R^(4A) can be OH. In otherembodiments, R^(4A) can be —OC(═O)R″^(B), wherein R″^(B) can be anoptionally substituted C₁₋₂₄ alkyl. In some embodiments, R^(4A) can be—OC(═O)R″^(B), wherein R″^(B) can be an unsubstituted C₁₋₄ alkyl. Instill other embodiments, R^(4A) can be halo. In some embodiments, R^(4A)can be F. In other embodiments, R^(4A) can be Cl. In some embodiments,R^(4A) can be N₃. In some embodiments, R^(4A) can be NR″^(B1)R″^(B2).For example, R^(4A) can be NH₂. Other examples can be a mono-substitutedC₁₋₆ alkyl-amine or a di-substituted C₁₋₆ alkyl-amine. In otherembodiments, R^(4A) can be hydrogen (H).

In still other embodiments, R^(4A) can be an optionally substitutedO-linked amino acid, such as a O-linked alpha-amino acid. In someembodiments, the O-linked amino acid can have the structure

wherein R^(42A) can be selected from hydrogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₁₋₆ haloalkyl, an optionallysubstituted C₃₋₆ cycloalkyl, an optionally substituted C₆ aryl, anoptionally substituted C₁₀ aryl and an optionally substituted aryl(C₁₋₆alkyl); and R^(43A) can be hydrogen or an optionally substituted C₁₋₄alkyl; or R^(42A) and R^(43A) can be taken together to form anoptionally substituted C₃₋₆ cycloalkyl.

When R^(42A) is substituted, R^(42A) can be substituted with one or moresubstituents selected from N-amido, mercapto, alkylthio, an optionallysubstituted aryl, hydroxy, an optionally substituted heteroaryl,O-carboxy and amino. In some embodiments, R^(42A) can be anunsubstituted C₁₋₆ alkyl, such as those described herein. In someembodiments, R^(42A) can be hydrogen. In other embodiments, R^(42A) canbe methyl. In some embodiments, R^(43A) can be hydrogen. In otherembodiments, R^(43A) can be an optionally substituted C₁₋₄ alkyl, suchas methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl.In some embodiments, R^(43A) can be methyl. Depending on the groups thatare selected for R^(42A) and R^(43A), the carbon to which R^(42A) andR^(43A) are attached may be a chiral center. In some embodiment, thecarbon to which R^(42A) and R^(43A) are attached may be a (R)-chiralcenter. In other embodiments, the carbon to which R^(42A) and R^(43A)are attached may be a (S)-chiral center.

Examples of suitable

include the following:

In some embodiments, R^(5A) can be H. In other embodiments, R^(5A) canbe halo, including F and Cl. In still other embodiments, R^(5A) can bean optionally substituted C₁₋₆ alkyl. For example, R^(5A) can be asubstituted or unsubstituted version of the following: methyl, ethyl,n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, pentyl (branchedor straight) and hexyl (branched or straight). In some embodiments,R^(5A) can be a halo-substituted C₁₋₆ alkyl, such as —CH₂F. In yet stillother embodiments, R^(5A) can be an optionally substituted C₂₋₆ alkenyl.In some embodiments, R^(5A) can be an optionally substituted C₂₋₆alkynyl. For example, R^(5A) can be ethynyl. In some embodiments R^(5A)can be hydroxy (OH).

In some embodiments,

can be both absent such that a compound of Formula (I) has thestructure:

When

are both absent, the 3′-position can have various groups present. Insome embodiments, R^(3A) can be H. In other embodiments, R^(3A) can behalo. For example, R^(3A) can be fluoro (F) or chloro (Cl). In stillother embodiments, R^(3A) can be OH. In some embodiments, R^(3A) can be—OC(═O)R″^(A), wherein R″^(A) can be an optionally substituted C₁₋₂₄alkyl. In some embodiments, R^(3A) can be —OC(═O)R″^(A), wherein R″^(A)can be an unsubstituted C₁₋₄ alkyl. In other embodiments, R^(3A) can bean optionally substituted O-linked amino acid, such as an optionallysubstituted O-linked alpha-amino acid. The optionally substitutedO-linked amino acid can have the structure:

wherein R^(44A) can be selected from hydrogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₁₋₆ haloalkyl, an optionallysubstituted C₃₋₆ cycloalkyl, an optionally substituted C₆ aryl, anoptionally substituted C₁₀ aryl and an optionally substituted aryl(C₁₋₆alkyl); and R^(45A) can be hydrogen or an optionally substituted C₁₋₄alkyl; or R^(44A) and R^(45A) can be taken together to form anoptionally substituted C₃₋₆ cycloalkyl.

When R^(44A) is substituted, R^(44A) can be substituted with one or moresubstituents selected from N-amido, mercapto, alkylthio, an optionallysubstituted aryl, hydroxy, an optionally substituted heteroaryl,O-carboxy and amino. In some embodiments, R^(44A) can be anunsubstituted C₁₋₆ alkyl, such as those described herein. In someembodiments, R^(44A) can be hydrogen. In other embodiments, R^(44A) canbe methyl. In some embodiments, R^(45A) can be hydrogen. In otherembodiments, R^(45A) can be an optionally substituted C₁₋₄ alkyl, suchas methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl.In some embodiments, R^(45A) can be methyl. Depending on the groups thatare selected for R^(44A) and R^(45A), the carbon to which R^(44A) andR^(45A) are attached may be a chiral center. In some embodiment, thecarbon to which R^(44A) and R^(45A) are attached may be a (R)-chiralcenter. In other embodiments, the carbon to which R^(44A) and R^(45A)are attached may be a (S)-chiral center.

Examples of suitable

include the following:

In some embodiments, R^(3A) and R^(4A) can be each an oxygen atomconnected via a carbonyl to form a 5-membered ring.

In some embodiments, R^(2A) can be fluoro and R^(3A) can be fluoro. Insome embodiments, R^(2A) can be fluoro and R^(4A) can be fluoro. In someembodiments, R^(2A) can be fluoro, R^(3A) can be fluoro and R^(5A) canbe an optionally substituted C₁₋₆ alkyl, an optionally substituted C₂₋₆alkenyl and an optionally substituted C₂₋₆ alkynyl. In some embodiments,R^(2A) can be fluoro, R^(4A) can be fluoro and R^(5A) can be anoptionally substituted C₁₋₆ alkyl, an optionally substituted C₂₋₆alkenyl and an optionally substituted C₂₋₆ alkynyl. In some embodiments,R^(2A) can be fluoro, R^(3A) can be fluoro and R^(4A) can be OH or—OC(═O)R″^(B). In some embodiments, R^(2A) can be fluoro, R^(3A) can beOH or —OC(═O)R″^(A) and R^(4A) can be fluoro. In some embodiments,R^(4A) and R^(5A) can be each F. In some embodiments, R^(2A) can be*—(CH₂)₁₋₆halogen (for example, —CH₂F), R^(3A) can be OH, —OC(═O)R″^(A)or an optionally substituted O-linked amino acid and R^(4A) can be OH.In some embodiments, R^(2A) can be —(CH₂)₁₋₆halogen (for example,—CH₂F), R^(3A) can be OH, —OC(═O)R″^(A) or an optionally substitutedO-linked amino acid, R^(4A) can be OH, and R^(5A) can be anunsubstituted C₁₋₆ alkyl. In some embodiments, R^(2A) can be —(CH₂)₁₋₆N₃(such as, —CH₂N₃), R^(3A) can be OH and R^(4A) can be fluoro.

In some embodiments,

can be each a single bond such that a compound of Formula (I) has thestructure:

When

are each a single bond, R^(3A) can be oxygen (O). In some embodiments,when

are each a

single bond, R^(1B) can be O⁻ or OH. In other embodiments, when

are each a single

bond, R^(1B) can be an —O-optionally substituted C₁₋₆ alkyl. Forexample, R^(1B) can be an —O-unsubstituted C₁₋₆ alkyl.

In some embodiments, when

are each a single bond, R^(1B) can be

In other embodiments, R^(1B) can be

For example, R^(1B) can be an optionally substitutedisopropyloxycarbonyloxymethyloxy or an optionally substitutedpivaloyloxymethyloxy group. In still some embodiments, R^(1B) can be

An optionally substituted S-acylthioethyl (SATE) group is an example ofa

group. In yet still other embodiments, R^(1B) can be an optionallysubstituted N-linked amino acid or an optionally substituted N-linkedamino acid ester derivative, such as an optionally substituted N-linkedalpha-amino acid or an optionally substituted N-linked alpha-amino acidester derivative.

Examples of an optionally substituted N-linked amino acids and anoptionally substituted N-linked amino acid ester derivatives aredescribed herein. In some embodiments, R^(1B) can be selected fromalanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine,proline, serine, tyrosine, arginine, histidine, isoleucine, leucine,lysine, methionine, phenylalanine, threonine, tryptophan, valine andester derivatives thereof. In some embodiments, R^(1B) can be anoptionally substituted version of the following: N-alanine isopropylester, N-alanine cyclohexyl ester, N-alanine neopentyl ester, N-valineisopropyl ester and N-leucine isopropyl ester. In some embodiments,R^(1B) can have the structure

wherein R^(10B) can be selected from hydrogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted aryl, an optionally substituted aryl(C₁₋₆ alkyl) and anoptionally substituted haloalkyl; R^(11B) can be selected from hydrogen,an optionally substituted C₁₋₆ alkyl, an optionally substituted C₁₋₆haloalkyl, an optionally substituted C₃₋₆ cycloalkyl, an optionallysubstituted C₆ aryl, an optionally substituted C₁₀ aryl and anoptionally substituted aryl(C₁₋₆ alkyl); and R^(12B) can be hydrogen oran optionally substituted C₁₋₄ alkyl; or R^(11B) and R^(12B) can betaken together to form an optionally substituted C₃₋₆ cycloalkyl.

As described herein, R^(11B) can be substituted. Examples ofsubstituents include one or more substituents selected from N-amido,mercapto, alkylthio, an optionally substituted aryl, hydroxy, anoptionally substituted heteroaryl, O-carboxy and amino. In someembodiments, R^(11B) can be an unsubstituted C₁₋₆ alkyl, such as thosedescribed herein. In some embodiments, R^(11B) can be hydrogen. In otherembodiments, R^(11B) can be methyl. In some embodiments, R^(10B) can bean optionally substituted C₁₋₆ alkyl. In some embodiments, R^(10B) canbe methyl, ethyl, isopropyl or neopentyl. In other embodiments, R^(10B)can be an optionally substituted C₃₋₆ cycloalkyl. Examples of optionallysubstituted C₃₋₆ cycloalkyl include optionally substituted variants ofthe following: cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Insome embodiments, R^(10B) can be an optionally substituted cyclohexyl.In still other embodiments, R^(10B) can be an optionally substitutedaryl, such as phenyl and naphthyl. In yet still other embodiments,R^(10B) can be an optionally substituted aryl(C₁₋₆ alkyl), for example,an optionally substituted benzyl. In some embodiments, R^(10B) can be anoptionally substituted C₁₋₆ haloalkyl, for example, CF₃. In someembodiments, R^(12B) can be hydrogen. In other embodiments, R^(12B) canbe an optionally substituted C₁₋₄ alkyl, such as methyl, ethyl,n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. In someembodiments, R^(12B) can be methyl. In some embodiments, R^(11B) andR^(12B) can be taken together to form an optionally substituted C₃₋₆cycloalkyl. Depending on the groups that are selected for R^(11B) andR^(12B), the carbon to which R^(11B) and R^(12B) are attached may be achiral center. In some embodiment, the carbon to which R^(11B) andR^(12B) are attached may be a (R)-chiral center. In other embodiments,the carbon to which R^(11B) and R^(12B) are attached may be a (S)-chiralcenter.

Examples of suitable

groups include the following:

In some embodiments, R^(1B) can be

In some embodiments, R^(9B) can be hydrogen. In other embodiments,R^(9B) can be an optionally substituted C₁₋₂₄ alkyl. In still otherembodiments, R^(9B) can be an optionally substituted aryl, for example,an optionally substituted phenyl. In some embodiments, R^(9B) can be anoptionally substituted C₁₋₆ alkyl. In some embodiments, R^(9B) can be anunsubstituted C₁₋₆ alkyl. In some embodiments, u can be 3. In otherembodiments, u can be 4. In still other embodiments, u can be 5.

In some embodiments, Z^(1B) can be oxygen (O). In other embodiments,Z^(1B) can be S (sulfur).

A variety of substituents can be present at the 1′-position of thepentose ring. In some embodiments, R^(A) can be hydrogen. In someembodiments, R^(A) can be deuterium. In still other embodiments, R^(A)can be an unsubstituted C₁₋₃ alkyl (such as methyl, ethyl, n-propyl andiso-propyl). In yet still other embodiments, R^(A) can be anunsubstituted C₂₋₄ alkenyl (for example, ethenyl, propenyl (branched orstraight) and butenyl (branched or straight)). In some embodiments,R^(A) can be an unsubstituted C₂₋₃ alkynyl (such as ethynyl and propynyl(branched or straight)). In other embodiments, R^(A) can be anunsubstituted cyano.

Various optionally substituted heterocyclic bases can be attached to thepentose ring. In some embodiments, one or more of the amine and/or aminogroups of the optionally substituted heterocyclic base may be protectedwith a suitable protecting group. For example, an amino group may beprotected by transforming the amine and/or amino group to an amide or acarbamate. In some embodiments, an optionally substituted heterocyclicbase or an optionally substituted heterocyclic base can include a groupthat improves the solubility of the compound (for example,—(CH₂)₁₋₂—O—P(═O)(OW^(1A))₂). In some embodiments, an optionallysubstituted heterocyclic base or an optionally substituted heterocyclicbase with one or more protected amino groups can have one of thefollowing structures:

wherein: R^(A2) can be selected from hydrogen, halogen and NHR^(J2),wherein R^(J2) can be selected from hydrogen, —C(═O)R^(K2) and—C(═O)OR^(L2); R^(B2) can be halogen or NHR^(W2), wherein R^(W2) can beselected from hydrogen, an optionally substituted C₁₋₆ alkyl, anoptionally substituted C₂₋₆ alkenyl, an optionally substituted C₃₋₈cycloalkyl, —C(═O)R^(M2) and —C(═O)OR^(N2); R^(C2) can be hydrogen orNHR^(O2), wherein R^(O2) can be selected from hydrogen, —C(═O)R^(P2) and—C(═O)OR^(Q2); R^(D2) can be selected from hydrogen, deuterium, halogen,an optionally substituted C₁₋₆ alkyl, an optionally substituted C₂₋₆alkenyl and an optionally substituted C₂₋₆ alkynyl; R^(E2) can beselected from hydrogen, hydroxy, an optionally substituted C₁₋₆ alkyl,an optionally substituted C₃₋₈ cycloalkyl, —C(═O)R^(R2) and—C(═O)OR^(S2); R^(F2) can be selected from hydrogen, halogen, anoptionally substituted C₁₋₆ alkyl, an optionally substituted C₂₋₆alkenyl and an optionally substituted C₂₋₆ alkynyl; Y² and Y³ can beindependently N (nitrogen) or CR^(I2), wherein R^(I2) can be selectedfrom hydrogen, halogen, an optionally substituted C₁₋₆ alkyl, anoptionally substituted C₂₋₆-alkenyl and an optionally substitutedC₂₋₆-alkynyl; W¹ can be NH, —NCH₂—OC(═O)CH(NH₂)—CH(CH₃)₂ or—(CH₂)₁₋₂—O—P(═O)(OW^(1A))₂, wherein W^(1A) can be selected from absent,hydrogen and an optionally substituted C₁₋₆ alkyl; R^(G2) can be anoptionally substituted C₁₋₆ alkyl; R^(H2) can be hydrogen or NHR^(T2),wherein R^(T2) can be independently selected from hydrogen, —C(═O)R^(U2)and —C(═O)OR^(V2); and R^(K2), R^(L2), R^(M2), R^(N2), R^(P2), R^(Q2),R^(R2), R^(S2), R^(Y2) and R^(V2) can be independently selected fromhydrogen, C₁₋₆ alkyl, C₂₋₆ alkenyl, C₂₋₆ alkynyl, C₃₋₆ cycloalkyl, C₃₋₆cycloalkenyl, C₆₋₁₀ aryl, heteroaryl, heterocyclyl, aryl(C₁₋₆ alkyl),heteroaryl(C₁₋₆ alkyl) and heterocyclyl(C₁₋₆ alkyl). In someembodiments, the structures shown above can be modified by replacing oneor more hydrogens with substituents selected from the list ofsubstituents provided for the definition of “substituted.” In someembodiments of B^(1A), a hydrogen can be replaced with a deuterium.Those skilled in the art understand that when W^(1A) is absent, theoxygen atom will have an associated negative charge.

In some embodiments, B^(1A) can be an optionally substituted purinebase.

In other embodiments, B^(1A) can be an optionally substituted pyrimidinebase. In some embodiments, B^(1A) can be

In other embodiments, B^(1A) can be

In still other embodiments, B^(1A) can be

In yet still other embodiments, B^(1A) can be

wherein W¹ can be —NCH₂—OC(═O)CH(NH₂)—CH(CH₃)₂ or—(CH₂)₁₋₂—O—P(═O)(OW^(1A))₂. In some embodiments, B^(1A) can be

for example,

In other embodiments, R^(D2) can be hydrogen. In still otherembodiments, B^(1A) can be

In some embodiments, R^(B2) can be NH₂. In other embodiments, R^(B2) canbe NHR^(W2), wherein R^(W2) can be —C(═O)R^(M2) or —C(═O)OR^(N2). Instill other embodiments, B^(1A) can be

In some embodiments, B^(1A) can be

In some embodiments, when R^(2A) is halo (such as fluoro);

are both absent; Z¹ is absent; O¹ is OR^(1A); B^(1A) is selected from anoptionally substituted

an optionally substituted

an optionally substituted

an optionally substituted

an optionally substituted

and an optionally substituted

wherein R^(a2) is an optionally substituted C₁₋₆ alkyl or an optionallysubstituted C₃₋₆ cycloalkyl, R^(a3) and R^(a4) are independentlyselected from hydrogen, an unsubstituted C₁₋₆ alkyl, an unsubstitutedC₃₋₆ alkenyl, an unsubstituted C₃₋₆ alkynyl and an unsubstituted C₃₋₆cycloalkyl, R^(a5) is NHR^(a8), and R^(a6) is hydrogen, halogen orNHR^(a9); R^(a7) is NHR^(a10); R^(a8) is selected from hydrogen, anoptionally substituted C₁₋₆ alkyl, an optionally substituted C₃₋₆alkenyl, an optionally substituted C₃₋₆ cycloalkyl, —C(═O)R^(a11) and—C(═O)OR^(a12); R^(a9) is selected from hydrogen, an optionallysubstituted C₁₋₆ alkyl, an optionally substituted C₃₋₆ alkenyl, anoptionally substituted C₃₋₆ cycloalkyl, —C(═O)R^(a3) and —C(═O)OR^(a14);R^(a10) is selected from hydrogen, an optionally substituted C₁₋₆ alkyl,an optionally substituted C₃₋₆ alkenyl, an optionally substituted C₃₋₆cycloalkyl, —C(═O)R^(a5) and —C(═O)OR^(a16); X^(a1) is N or —CR^(a17);R^(a17) is selected from hydrogen, halogen, an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₂₋₆ alkenyl and an optionallysubstituted C₂₋₆ alkynyl; R^(a11), R^(a12), R^(a13), R^(a14), R^(a15)and R^(a16) are independently selected from C₁₋₆ alkyl, C₂₋₆ alkenyl,C₂₋₆ alkynyl, C₃₋₆ cycloalkyl, C₃₋₆ cycloalkenyl, C₆₋₁₀ aryl,heteroaryl, heterocyclyl, aryl(C₁₋₆ alkyl), heteroaryl(C₁₋₆ alkyl) andheterocyclyl(C₁₋₆ alkyl); then R^(3A) is selected from hydrogen, halo,and an optionally substituted O-linked amino acid; and R^(4A) isselected from OH, halo, —OC(═O)R″^(A) and an optionally substitutedO-linked amino acid; or then R^(4A) is an optionally substitutedO-linked amino acid; and R^(3A) is selected from hydrogen, halo, OH,—OC(═O)R″^(A) and an optionally substituted O-linked amino acid; or thenR^(3A) and R^(4A) are both an oxygen atom connected via a carbonyl toform a 5-membered ring; or then R^(1A) is

wherein R^(6A) and R^(7A) are independently

wherein s is 1, 2 or

or then R^(1A) is

wherein R^(6A) and R^(7A) are taken together to form a moiety selectedfrom an optionally substituted

and an optionally substituted

wherein the oxygens connected to R^(6A) and R^(7A), the phosphorus andthe moiety form a six-membered to ten-membered ring system. In someembodiments, when R^(2A) is halo (such as fluoro);

are each a single bond; then R^(4A) is —OC(═O)R″^(B) or an optionallysubstituted O-linked amino acid. In some embodiments, when R^(2A) is anunsubstituted C₁₋₄ alkyl, an unsubstituted C₂₋₄ alkenyl, anunsubstituted C₂₋₄ alkynyl, —(CH₂)₁₋₆ halogen or —(CH₂)₁₋₆N₃;

are both absent; Z¹ is absent; O¹ is OR^(1A); R^(3A) is OH,—OC(═O)R″^(A) or an optionally substituted O-linked amino acid; andR^(4A) is halo; then R^(5A) is selected from an optionally substitutedC₁₋₆ alkyl, an optionally substituted C₂₋₆ alkenyl and an optionallysubstituted C₂₋₆ alkynyl. In some embodiments, when R^(2A) is anunsubstituted C₁₋₄ alkyl, an unsubstituted C₂₋₄ alkenyl, anunsubstituted C₂₋₄ alkynyl, —(CH₂)₁₋₆ halogen or —(CH₂)₁₋₆N₃;

are both absent; Z¹ is absent; O¹ is OR^(1A); R^(4A) is halo; and R^(5A)is hydrogen or halo; then R^(3A) is hydrogen or halo. In someembodiments, when R^(2A) is an unsubstituted C₁₋₄ alkyl, anunsubstituted C₂₋₄ alkenyl, an unsubstituted C₂₋₄ alkynyl, —(CH₂)₁₋₆halogen or —(CH₂)₁₋₆N₃;

are both absent; Z¹ is absent; O¹ is OR^(1A); R^(3A) is OH,—OC(═O)R″^(A) or an optionally substituted O-linked amino acid; R^(4A)is halo; R^(5A) is hydrogen or halo; and R^(1A) is

then at least one of R^(6A) and R^(7A) is

wherein R^(21A) is independently selected from an optionally substituted—O-heteroaryl and an optionally substituted —O-monocyclic heterocyclyl;or then at least one of R^(6A) and R^(7A) is

wherein s is 1, 2 or 3; or then at least one of R^(6A) and R^(7A) is

wherein s is 0 and R^(24A) is an optionally substituted —O-heteroaryl oran optionally substituted —O-monocyclic heterocyclyl. In someembodiments, when R^(2A) is an unsubstituted C₁₋₄ alkyl, anunsubstituted C₂₋₄ alkenyl, an unsubstituted C₂₋₄ alkynyl, —(CH₂)₁₋₆halogen or —(CH₂)₁₋₆N₃;

are both absent; Z¹ is absent; O¹ is OR^(1A); R^(3A) is OH,—OC(═O)R″^(A) or an optionally substituted O-linked amino acid; R^(4A)is halo; R^(5A) is hydrogen or halo; and R^(1A) is

then R^(8A) is

wherein R^(21A) is independently selected from an optionally substituted—O-heteroaryl and an optionally substituted —O-monocyclic heterocyclyl;or then R^(8A) is

wherein s is 1, 2 or 3; or then R^(8A) is

wherein s is 0 and R^(24A) is an optionally substituted —O-heteroaryl,an optionally substituted —O-monocyclic heterocyclyl or

In some embodiments, when

are both absent; Z¹ is absent; O¹ is OH; R^(2A) is methyl; R^(3A) is OH;then R^(4A) is halo, —OC(═O)R″^(B) or an optionally substituted O-linkedamino acid. In some embodiments, when

are both absent; Z¹ is absent; O¹ is OR^(1A); R^(2A) is halo (forexample, F); R^(3A) is OH or —OC(═O)R″^(A); R^(4A) is halo (for example,F); and R^(5A) is methyl, ethyl or ethenyl; then R^(1A) cannot beselected from hydrogen,

wherein R^(8A) is an unsubstituted aryl; R^(9A) is

and Z^(2A) is oxygen. In some embodiments, R^(1A) is not hydrogen (H),for example, when R^(3A) is halo (such as fluoro) and R^(4A) is OH. Insome embodiments, R^(1A) is not

wherein Z^(1A) is O and R^(6A) is

for example, when R^(4A) is halo (such as fluoro) and R^(3A) is OH. Insome embodiments, R^(2A) is not hydrogen (H). In some embodiments,R^(2A) is not halogen. In some embodiments, R^(2A) is not fluoro (F). Insome embodiments, R^(2A) is not —CN. In some embodiments, R^(2A) is not—CHF₂. In some embodiments, R^(2A) is not —CF₃. In some embodiments,R^(5A) is not hydrogen or halo. In some embodiments, R^(5A) is not —OH.In some embodiments, R^(4A) is not hydrogen (H). In some embodiments,R^(4A) is not halo. In some embodiments, R^(4A) is not fluoro (F). Insome embodiments, R^(4A) is not chloro (Cl). In some embodiments, R^(2A)is not an unsubstituted C₁₋₄ alkyl. In some embodiments, R^(2A) is notan unsubstituted C₂₋₄ alkenyl. In some embodiments, R^(2A) is not anunsubstituted C₂₋₄ alkynyl. In some embodiments, R^(2A) is not —(CH₂)₁₋₆halogen. In some embodiments, R^(2A) is not —(CH₂)₁₋₆N₃. In someembodiments, R^(4A) is not hydrogen, when R^(5A) is fluoro. In someembodiments, R^(6A) is not an optionally substituted aryl. In someembodiments, R^(6A) is not an unsubstituted aryl. In some embodiments,R^(9A) is not N-alanine isopropyl ester. In some embodiments, R^(5A) isnot an optionally substituted C₁₋₆ alkyl. For example, R^(5A) is not anunsubstituted C₁₋₆ alkyl, such as methyl. In some embodiments, B^(1A) isnot an optionally substituted uracil, for example, a halo-substituteduracil. In some embodiments, when R^(1A) is hydrogen, an optionallysubstituted acyl,

wherein R^(6A) can be

wherein R^(8A) is an unsubstituted or substituted phenyl or anunsubstituted or substituted naphthyl and R^(9A) is an optionallysubstituted N-linked amino acid or an optionally substituted N-linkedamino acid ester; R^(2A) is fluoro, R^(3A) is OH or —C(═O)-unsubstitutedor substituted phenyl; R^(4A) is fluoro; and R^(5A) is a C₁₋₄ alkyl(such as methyl); then B^(1A) cannot be an optionally substitutedpyrimidine base, such as

In some embodiments, when R^(1A) is

R^(2A) is hydrogen, R^(3A) is OH and R^(4A) is OH or halogen (such asF), then R^(5A) is not an optionally substituted C₁₋₆ alkyl, anoptionally substituted C₂₋₆ alkenyl or an optionally substituted C₂₋₆alkynyl. In some embodiments, a compound of Formulae (I) and/or (II), ora pharmaceutically acceptable salt of the foregoing, is not a compoundin WO 2013/092481 (filed Dec. 17, 2012), U.S. 2014/0178338 (filed Dec.17, 2013), U.S. 2013/0164261 (filed Dec. 20, 2012), WO 2014/100505(filed Dec. 19, 2013), WO 2013/096679 (filed Dec. 20, 2012), WO2013/142525 (filed Mar. 19, 2013), and/or WO 2014/209983 (filed Jun. 24,2014), WO 2014/209979 (filed Jun. 24, 2014) and/or U.S. 2015/0105341(filed Oct. 9, 2014), or a pharmaceutically acceptable salt of theforegoing.

Examples of compounds of Formula (I), or a pharmaceutically acceptablesalt thereof, include, but are not limited to:

or a pharmaceutically acceptable salt of the foregoing.

Additional examples of compounds of Formula (I), or a pharmaceuticallyacceptable salt thereof, include, but are not limited to:

or a pharmaceutically acceptable salt of the foregoing.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, may be selected from:

or a pharmaceutically acceptable salt of the foregoing.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, may be selected from:

or a pharmaceutically acceptable salt of the foregoing.

In some embodiments, a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, may be selected from:

or a pharmaceutically acceptable salt of the foregoing.Pharmaceutical Compositions

Some embodiments described herein relates to a pharmaceuticalcomposition, that can include an effective amount of one or morecompounds described herein (e.g., a compound of Formula (I), or apharmaceutically acceptable salt thereof) and a pharmaceuticallyacceptable carrier, diluent, excipient or combination thereof. In someembodiments, the pharmaceutical composition can include a singlediastereomer of a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, (for example, a single diastereomer is presentin the pharmaceutical composition at a concentration of greater than 99%compared to the total concentration of the other diastereomers). Inother embodiments, the pharmaceutical composition can include a mixtureof diastereomers of a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof. For example, the pharmaceutical composition caninclude a concentration of one diastereomer of >50%, ≧60%, ≧70%, ≧80%,≧90%, ≧95%, or ≧98%, as compared to the total concentration of the otherdiastereomers. In some embodiments, the pharmaceutical compositionincludes a 1:1 mixture of two diastereomers of a compound of Formula(I), or a pharmaceutically acceptable salt thereof.

The term “pharmaceutical composition” refers to a mixture of one or morecompounds disclosed herein with other chemical components, such asdiluents or carriers. The pharmaceutical composition facilitatesadministration of the compound to an organism. Pharmaceuticalcompositions can also be obtained by reacting compounds with inorganicor organic acids such as hydrochloric acid, hydrobromic acid, sulfuricacid, nitric acid, phosphoric acid, methanesulfonic acid, ethanesulfonicacid, p-toluenesulfonic acid and salicylic acid. Pharmaceuticalcompositions will generally be tailored to the specific intended routeof administration. A pharmaceutical composition is suitable for humanand/or veterinary applications.

The term “physiologically acceptable” defines a carrier, diluent orexcipient that does not abrogate the biological activity and propertiesof the compound.

As used herein, a “carrier” refers to a compound that facilitates theincorporation of a compound into cells or tissues. For example, withoutlimitation, dimethyl sulfoxide (DMSO) is a commonly utilized carrierthat facilitates the uptake of many organic compounds into cells ortissues of a subject.

As used herein, a “diluent” refers to an ingredient in a pharmaceuticalcomposition that lacks pharmacological activity but may bepharmaceutically necessary or desirable. For example, a diluent may beused to increase the bulk of a potent drug whose mass is too small formanufacture and/or administration. It may also be a liquid for thedissolution of a drug to be administered by injection, ingestion orinhalation. A common form of diluent in the art is a buffered aqueoussolution such as, without limitation, phosphate buffered saline thatmimics the composition of human blood.

As used herein, an “excipient” refers to an inert substance that isadded to a pharmaceutical composition to provide, without limitation,bulk, consistency, stability, binding ability, lubrication,disintegrating ability etc., to the composition. A “diluent” is a typeof excipient.

The pharmaceutical compositions described herein can be administered toa human patient per se, or in pharmaceutical compositions where they aremixed with other active ingredients, as in combination therapy, orcarriers, diluents, excipients or combinations thereof. Properformulation is dependent upon the route of administration chosen.Techniques for formulation and administration of the compounds describedherein are known to those skilled in the art.

The pharmaceutical compositions disclosed herein may be manufactured ina manner that is itself known, e.g., by means of conventional mixing,dissolving, granulating, dragee-making, levigating, emulsifying,encapsulating, entrapping or tableting processes. Additionally, theactive ingredients are contained in an amount effective to achieve itsintended purpose. Many of the compounds used in the pharmaceuticalcombinations disclosed herein may be provided as salts withpharmaceutically compatible counterions.

Multiple techniques of administering a compound exist in the artincluding, but not limited to, oral, rectal, topical, aerosol, injectionand parenteral delivery, including intramuscular, subcutaneous,intravenous, intramedullary injections, intrathecal, directintraventricular, intraperitoneal, intranasal and intraocularinjections.

One may also administer the compound in a local rather than systemicmanner, for example, via injection of the compound directly into theinfected area, often in a depot or sustained release formulation.Furthermore, one may administer the compound in a targeted drug deliverysystem, for example, in a liposome coated with a tissue-specificantibody. The liposomes will be targeted to and taken up selectively bythe organ.

The compositions may, if desired, be presented in a pack or dispenserdevice which may contain one or more unit dosage forms containing theactive ingredient. The pack may for example comprise metal or plasticfoil, such as a blister pack. The pack or dispenser device may beaccompanied by instructions for administration. The pack or dispensermay also be accompanied with a notice associated with the container inform prescribed by a governmental agency regulating the manufacture,use, or sale of pharmaceuticals, which notice is reflective of approvalby the agency of the form of the drug for human or veterinaryadministration. Such notice, for example, may be the labeling approvedby the U.S. Food and Drug Administration for prescription drugs, or theapproved product insert. Compositions that can include a compounddescribed herein formulated in a compatible pharmaceutical carrier mayalso be prepared, placed in an appropriate container, and labeled fortreatment of an indicated condition.

Synthesis

Compounds of Formula (I) and those described herein may be prepared invarious ways. General synthetic routes to the compound of Formula (I)and some examples of starting materials used to synthesize the compoundsof Formula (I) are shown in Scheme 1, 2, 3 and 4, and described herein.The routes shown and described herein are illustrative only and are notintended, nor are they to be construed, to limit the scope of the claimsin any manner whatsoever. Those skilled in the art will be able torecognize modifications of the disclosed syntheses and to devisealternate routes based on the disclosures herein; all such modificationsand alternate routes are within the scope of the claims.

Compounds of Formula (I) can be prepared using various methods known tothose skilled in the art. Examples of methods are shown in Schemes 1, 2,3 and 4. Suitable phosphorus containing precursors can be commerciallyobtained or prepared by synthetic methods known to those skilled in theart. Examples of general structures of phosphorus containing precursorsare shown in Schemes 1, 2, 3 and 4, and include phosphorochloridates andthiophosphorochloridates. Suitable phosphorochloridates andthiophosphorochloridates are commercially available and/or can besynthetically prepared.

As shown in Scheme 1, compounds of Formula (I), wherein the 4′-positionis a haloalkyl, can be prepared from a nucleoside, for example, anucleoside of Formula (A). In Scheme 1, R^(a), R^(3a), R^(4a), R^(5a),and B^(1a) can be the same as R^(A), R^(3A), R^(4A), R^(5A) and B^(1A)as described herein for Formula (I), and PG¹ is a suitable protectinggroup. A hydroxyalkyl group can be formed at the 4′-position of thepentose ring using suitable conditions known to those skilled in theart. Examples of suitable conditions for forming a hydroxyalkyl includethe use of 2-iodoxybenzoic acid (IBX) aqueous formaldehyde and sodiumborohydride. A compound of Formula (B) can be transformed to a haloalkylusing a suitable agent(s), for example, to an iodide using imidazole,triphenylphosphine and iodine; to a fluoro using diethylaminosulfurtrifluoride (DAST); or to a chloro using triphenylphosphine andcarbontetrachloride in dichloroethylene (DCE).

Compounds of Formula (I), where R^(2A) is a C₁₋₆ azidoalkyl, can beprepared from a nucleoside, for example, a nucleoside of Formula (A). InScheme 2, R^(a), R^(3a), R^(4a), R^(5a) and B^(1a) can be the same asR^(A), R^(3A), R^(4A), R^(5A) and B^(1A) as described herein for Formula(I), PG² can be a suitable protecting group and LG² can be a suitableleaving group. The 5′-position of the nucleoside can be oxidized to analdehyde using methods known to those skilled in the art. Suitableoxidation conditions include, but are not limited to, Moffatt oxidation,Swem oxidation and Corey-Kim oxidation; and suitable oxidizing agentsinclude, but are not limited to, Dess-Martin periodinane, IBX(2-iodoxybenzoic acid), TPAP/NMO (tetrapropylammoniumperruthenate/N-methylmorpholine N-oxide), Swern oxidation reagent, PCC(pyridinium chlorochromate), PDC (pyridinium dichromate), sodiumperiodate, Collin's reagent, ceric ammonium nitrate CAN, Na₂Cr₂O₇ inwater, Ag₂CO₃ on celite, hot HNO₃ in aqueous glyme, O₂-pyridine CuCl,Pb(OAc)₄-pyridine and benzoyl peroxide-NiBr₂. A hydroxymethyl group canbe added to the 4′-position of the pentose ring along with the reductionof the aldehyde to an alcohol. The hydroxymethyl group can be added viaa condensation reaction using formaldehyde and a base, such as sodiumhydroxide. After addition of the hydroxymethyl group, reduction of theintermediate compound with a 4′-hydroxymethyl group can be conductedusing a reducing reagent. Examples of suitable reducing agents include,but are not limited to, NaBH₄ and LiAlH₄. A suitable leaving group, suchas a triflate, can be formed by replacing the hydrogen of thehydroxymethyl group attached to the 4′-position, and the oxygen attachedto the 5′-position can be protected with a suitable protecting group(for example, by cyclization with the base, B^(1a), or with a separateprotecting group). The leaving group can be replaced with an azido groupusing a metal azide reagent, for example, sodium azide. A C₁₋₆azidoalkyl at the 4′-position can be reduced to a C₁₋₆ aminoalkyl.Various reduction agents/conditions known to those skilled in the artcan be utilized. For example, the azido group can be reduced to an aminogroup via hydrogenation (for example, H₂—Pd/C or HCO₂NH₄—Pd/C),Staudinger Reaction, NaBH₄/CoCl₂.6H₂O, Fe/NH₄Cl or Zn/NH₄Cl.

Compounds of Formula (I) having a phosphorus containing group attachedto the 5′-position of the pentose ring can be prepared using variousmethods known to those skilled in the art. Examples of methods are shownin Schemes 3 and 4. In Schemes 3 and 4, R^(a), R^(2a), R^(3a), R^(4a),R^(5a) and B^(1a) can be the same as R^(A), R^(2A), R^(3A), R^(4A),R^(5A) and B^(1A) as described herein for Formulae (I). A phosphoruscontaining precursor can be coupled to the nucleoside, for example, acompound of Formula (B). Following the coupling of the phosphoruscontaining precursor, any leaving groups can be cleaved under suitableconditions, such as hydrolysis. Further phosphorus containing groups canbe added using methods known to those skilled in the art, for exampleusing a pyrophosphate. If desired, one or more bases can be used duringthe addition of each phosphorus-containing group. Examples of suitablebases are described herein.

In some embodiments, an alkoxide can be generated from a compound ofFormula (C) using an organometallic reagent, such as a Grignard reagent.The alkoxide can be coupled to the phosphorus containing precursor.Suitable Grignard reagents are known to those skilled in the art andinclude, but are not limited to, alkylmagnesium chlorides andalkylmagnesium bromides. In some embodiments, an appropriate base can beused. Examples of suitable bases include, but are not limited to, anamine base, such as an alkylamine (including mono-, di- andtri-alkylamines (e.g., triethylamine)), optionally substituted pyridines(e.g. collidine) and optionally substituted imidazoles (e.g.,N-methylimidazole)). Alternatively, a phosphorus containing precursorcan be added to the nucleoside and form a phosphite. The phosphite canbe oxidized to a phosphate using conditions known to those skilled inthe art. Suitable conditions include, but are not limited to,meta-chloroperoxybenzoic acid (MCPBA) and iodine as the oxidizing agentand water as the oxygen donor.

When compounds of Formula (I) have Z^(1A), Z^(2A) or Z^(3A) beingsulfur, the sulfur can be added in various manners known to thoseskilled in the art. In some embodiments, the sulfur can be part of thephosphorus containing precursor, for example,

Alternatively, the sulfur can be added using a sulfurization reagent.Suitable sulfurization agents are known to those skilled in the art, andinclude, but are not limited to, elemental sulfur, Lawesson's reagent,cyclooctasulfur, 3H-1,2-Benzodithiole-3-one-1,1-dioxide (Beaucage'sreagent),3-((N,N-dimethylaminomethylidene)amino)-3H-1,2,4-dithiazole-5-thione(DDTT) and bis(3-triethoxysilyl)propyl-tetrasulfide (TEST).

As described herein, in some embodiments, R^(3A) and R^(4A) can be eachan oxygen atom, wherein the oxygen atoms are linked together by acarbonyl groups. The —O—C(═O)—O— group can be formed using methods knownto those skilled in the art. For example, a compound of Formula (I),wherein R^(3A) and R^(4A) are both hydroxy groups, can be treated with1,1′-carbonyldiimidazole (CDI).

In some embodiments, the 2′-position and/or the 3′-position of thepentose ring can have an optionally substituted —O-acyl group attached,for example, —OC(═O)R″^(A) The optionally substituted —O-acyl group canbe formed at the 2′- and/or 3′-position using various methods known tothose skilled in the art. As an example, a compound of Formulae (I),wherein the 2′-position and the 3′-position each have an hydroxy groupattached, can be treated with an alkyl anhydride (e.g., acetic anhydrideand propionic anhydride) or an alkyl acid chloride (e.g.,acetylchloride). If desired, a catalyst can be used to facilitate thereaction. An example of suitable catalyst is 4-dimethylaminopyridine(DMAP). Alternatively, the optionally substituted —O-acyl group group(s)can be formed at the 2′- and 3′-positions by reacting an alkyl acid(e.g. acetic acid and propionic acid) in the presences of a carbodiimideor a coupling reagent. Examples of carbodiimides include, but are notlimited to, N,N′-dicyclohexylcarbodiimide (DCC),N,N′-diisopropylcarbodiimide (DIC) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC).

To reduce the formation of side products, one or more the groupsattached to the pentose ring can be protected with one or more suitableprotecting groups and/or any —NH and/or NH₂ groups present on theB^(1a), can be protected with one or more suitable protecting groups. Asan example, if 2′-position and/or the 3′-position is/are hydroxygroup(s), the hydroxy group(s) can be protected with suitable protectinggroups, such as triarylmethyl and/or silyl groups. Examples oftriarylmethyl groups include but are not limited to, trityl,monomethoxytrityl (MMTr), 4,4′-dimethoxytrityl (DMTr),4,4′,4″-trimethoxytrityl (TMTr), 4,4′,4″-tris-(benzoyloxy)trityl (TBTr),4,4′,4″-tris(4,5-dichlorophthalimido)trityl (CPTr),4,4′,4″-tris(levulinyloxy)trityl (TLTr),p-anisyl-1-naphthylphenylmethyl, di-o-anisyl-1-naphthylmethyl,p-tolyldipheylmethyl, 3-(imidazolylmethyl)-4,4′-dimethoxytrityl,9-phenylxanthen-9-yl (Pixyl), 9-(p-methoxyphenyl) xanthen-9-yl (Mox),4-decyloxytrityl, 4-hexadecyloxytrityl, 4,4′-dioctadecyltrityl,9-(4-octadecyloxyphenyl)xanthen-9-yl,1,1′-bis-(4-methoxyphenyl)-1′-pyrenylmethyl,4,4′,4″-tris-(tert-butylphenyl)methyl (TTTr) and4,4′-di-3,5-hexadienoxytrityl. Examples of suitable silyl groups aredescribed herein and include trimethylsilyl (TMS),tert-butyldimethylsilyl (TBDMS), triisopropylsilyl (TIPS),tert-butyldiphenylsilyl (TBDPS), tri-iso-propylsilyloxymethyl and[2-(trimethylsilyl)ethoxy]methyl. Alternatively, R^(3A) and/or R^(4A)can be protected by a single achiral or chiral protecting group, forexample, by forming an orthoester, a cyclic acetal or a cyclic ketal.Suitable orthoesters include methoxymethylene acetal, ethoxymethyleneacetal, 2-oxacyclopentylidene orthoester, dimethoxymethylene orthoester,1-methoxyethylidene orthoester, 1-ethoxyethylidene orthoester,methylidene orthoester, phthalide orthoester 1,2-dimethoxyethylideneorthoester, and alpha-methoxybenzylidene orthoester; suitable cyclicacetals include methylene acetal, ethylidene acetal, t-butylmethylideneacetal, 3-(benzyloxy)propyl acetal, benzylidene acetal,3,4-dimethoxybenzylidene acetal and p-acetoxybenzylidene acetal; andsuitable cyclic ketals include 1-t-butylethylidene ketal,1-phenylethylidene ketal, isopropylidene ketal, cyclopentylidene ketal,cyclohexylidene ketal, cycloheptylidene ketal and1-(4-methoxyphenyl)ethylidene ketal.

EXAMPLES

Additional embodiments are disclosed in further detail in the followingexamples, which are not in any way intended to limit the scope of theclaims.

Example 1 Compound 1

To a solution of 1-1 (100.0 g, 378.7 mmol) in pyridine (750 mL) wasadded DMTrCl (164.9 g, 487.8 mmol). The solution was stirred at RT for15 h. MeOH (300 mL) was added, and the mixture was concentrated todryness under reduced pressure. The residue was dissolved in EA andwashed with water. The organic layer was dried over Na₂SO₄ andconcentrated. The residue was dissolved in DCM (500 mL). To thissolution were added imidazole (44.3 g, 650.4 mmol) and TBSCl (91.9 g,609.8 mmol). The mixture was stirred at RT for 14 h. The solution waswashed with NaHCO₃ and brine. The organic layer was dried over Na₂SO₄,and concentrated to give the crude product as a light yellow solid. Thecrude (236.4 g, 347.6 mmol) was dissolved in 80% HOAc aqueous solution(500 mL). The mixture was stirred at RT for 15 h. The mixture wasdiluted with EA, and washed with NaHCO₃ solution and brine. The organiclayer was dried over Na₂SO₄ and purified on a silica gel columnchromatography (1-2% MeOH in DCM) to give 1-2 (131.2 g, 91.9%) as alight yellow solid. ESI-MS: m/z 802 [M+H]⁺.

To a solution of 1-2 (131.2 g, 346.9 mmol) in anhydrous CH₃CN (1200 mL)was added IBX (121.2 g, 432.8 mmol) at RT. The mixture was refluxed for3 h and then cooled to 0° C. The precipitate was filtered, and thefiltrate was concentrated to give the crude aldehyde (121.3 g) as ayellow solid. The aldehyde was dissolved in 1,4-dioxane (1000 mL). 37%CH₂O (81.1 mL, 1.35 mmol) and 2M NaOH aqueous solution (253.8 mL, 507.6mmol) were added. The mixture was stirred at RT for 2 h., and thenneutralized with AcOH to pH=7. To the solution were added EtOH (400 mL)and NaBH₄ (51.2 g, 1.35 mol). The mixture was stirred at RT for 30 mins,the reaction was quenched with sat. aq. NH₄Cl. The mixture was extractedwith EA. The organic layer was dried over Na₂SO₄ and concentrated. Theresidue was purified by silica gel column chromatography (1-3% MeOH inDCM) to give 1-3 (51.4 g, 38.9%) as a white solid.

To a solution of 1-3 (51.4 g, 125.9 mmol) in anhydrous DCM (400 mL) wereadded pyridine (80 mL) and DMTrCl (49.1 g, 144.7 mmol) at 0° C. Thereaction was stirred at RT for 14 h, and then treated with MeOH (30 mL).The solvent was removed, and the residue was purified by silica gelcolumn chromatography (1-3% MeOH in DCM) to give the mono-DMTr protectedintermediate as a yellow foam (57.4 g, 62.9%). The intermediate (57.4 g,82.8 mmol) was dissolved in CH₂Cl₂ (400 mL), and imidazole (8.4 g, 124.2mmol), TBDPSCl (34.1 g, 124.2 mmol) were added. The mixture was stirredat RT for 14 h. The precipitate was filtered off, and the filtrate waswashed with brine and dried with Na₂SO₄. The solvent was removed to givea residue (72.45 g) as a white solid. The residue was dissolved in 80%HOAc aqueous solution (400 mL). The mixture was stirred RT for 15 h. Themixture was diluted with EA and washed with NaHCO₃ solution and brine.The organic layer was dried over Na₂SO₄ and purified by silica gelcolumn chromatography (1-2% MeOH in DCM) to give 1-4 (37.6 g, 84.2%) asa white solid.

A solution of 1-4 (700 mg, 1.09 mmol) in anhydrous dichloromethane wasadded Dess-Martin reagent (919 mg, 2.16 mmol) at 0° C. The mixture wasstirred at RT for 30 mins. The reaction was quenched with sat. sodiumhydrogen carbonate and sodium thiosulfate solution, and extracted withEA. The organic layers were concentrated to give the crude aldehyde,which was used for next step without purification. A solution ofMePPh₃Br (3.88 g, 10.87 mmol) in anhydrous THF was treated with asolution of t-BuOK (9.81 mL, 9.81 mmol) in THF at 0° C. The mixture waswarmed to RT for 1 h. After cooling to 0° C. for 1 h, a solution of thealdehyde (700 mg, 1.09 mmol) in THF was added. The mixture was stirredovernight at RT. The reaction was quenched with sat. ammonium chloridesolution, and extracted with EA. The organic layers were purified bycolumn chromatography to give 1-5 (167 mg, 30%).

To a solution of 1-5 (450 mg, 0.69 mmol) in MeOH (10 mL) was added Pd/C(200 mg) at RT. The reaction mixture was stirred at RT for 1 h under H₂(balloon). Then the mixture was filtered and the filtrate wasconcentrated to give the crude 1-6 (440 mg, 97.1%) as a white solid.

A solution of 1-6 (317 mg, 0.49 mmol), TPSCl (373 mg, 1.23 mmol), DMAP(150 mg, 1.23 mmol) and TEA (124 mg, 1.23 mmol) in anhydrous MeCN wasstirred at RT overnight. The reaction was quenched with NH₃.H₂O, andthen stirred at RT for 3 h. The solvent was removed under reducedpressure. The residue was purified by column chromatography to give 1-7(200 mg, 63%).

To a solution of 1-7 (280 mg, 0.44 mmol) in MeOH (10 mL) was added NH₄F(1.0 g, 27.0 mmol) at RT. The mixture was refluxed for 12 h. The mixturewas filtered, and the filtrate was concentrated. The residue waspurified on a silica gel column (10% MeOH in DCM) to give compound 1 (81mg, 63.3%) as a white solid. ESI-MS: m/z 291.8 [M+H]⁺.

Example 2 Compound 2

To a solution of 2-1 (2.5 g, 4.04 mmol) in DMF was added NaH (170 mg,4.24 mmol, 60% purity) at 0° C. The mixture was stirred for 3 h at RT.NaI (6.1 g, 40.4 mmol) was added at RT and stirred for 3 h. The reactionwas diluted with water and extracted with EA. The organic layer wasdried over anhydrous Na₂SO₄, and concentrated at low pressure to give2-2 (1.7 g, 94%) as a yellow solid.

To a solution of 2-2 (1.7 g, 3.81 mmol) in THF (5 mL) was added 2 M NaOHsolution (4.5 mL) at 0° C. The solution was stirred for 2 h at RT. Themixture was adjusted to pH=7, and concentrated under reduced pressure.The mixture was partitioned between DCM and water. The DCM layer wasdried with high vacuum to give 2-3 (1.2 g, 68%) as a white solid, whichwas used without further purification.

To a solution of 2-3 (1.2 g, 2.58 mmol) in EtOH (20 mL) was addedNH₄COOH (650 mg, 7.75 mmol) and Pd/C (120 mg). The mixture was stirredunder H₂ (30 psi) for 1.5 h at RT. The suspension was filtered, and thefiltrate was concentrated at a low pressure. The residue was purified onsilica gel column (0.5% TEA and 1% MeOH in DCM) to give 2-4 (545 mg,62%). ESI-MS: m/z 361.2 [M+23]⁺.

Compound 2-4 was dissolved in 80% aq. HCOOH (20 mL) and kept at 20° C.for 18 h. After cooling to RT, the solvent was removed in vacuo, and theresidue co-evaporated with toluene (3×25 mL). The residue was dissolvedin water (3 mL) and concentrated aqueous NH₄OH (1 mL) was added. After 2h at 20° C., the solvent was removed in vacuo. The residue was purifiedby flash chromatography using a 5 to 50% gradient of methanol in DCM togive purified compound 2 (14 mg) as a white solid.

Example 3 Compound 4

Compound 4-1 (5.0 g, 8.5 mmol) and 2-amino-6-chloropurine (3.0 g, 17.7mmol) were co-concentrated with anhydrous toluene for 3 times. To astirred suspension of the mixture in anhydrous MeCN (50 mL) was addedDBU (7.5 g, 49 mmol) at 0° C. The mixture was stirred at 0° C. for 15mins, and TMSOTf (15 g, 67.6 mmol) was added dropwise at 0° C. Themixture was stirred at 0° C. for 15 mins and then heated to 70° C.overnight. The mixture was cooled to RT, and diluted with EA (100 mL).The solution was washed with sat. NaHCO₃ solution and brine. The organiclayer was dried over Na₂SO₄ and then concentrated at low pressure. Theresidue was purified by column on silica gel (PE/EA: from 15/1 to 3/1)to give 4-2 (2.5 g, 46.3%) as a white foam.

To a solution of 4-2 (10 g, 15.7 mmol), AgNO₃ (8.0 g, 47 mmol) andcollidine (10 mL) in anhydrous DCM (20 mL) was added MMTrCl (14.5 g, 47mmol) in small portions under N₂. The mixture was stirred at RTovernight. The mixture was filtered, and the filtrate was washed withsat. NaHCO₃ aqueous and brine. The organic layer was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by silica gel column (PE/ME=20/1 to 8/1) to give 4-3 (10 g,70%) as a yellow solid.

To a solution of 3-hydroxy-propionitrile (3.51 g, 49.4 mmol) inanhydrous THF (100 mL) was added NaH (2.8 g, 70 mmol) at 0° C., and themixture was stirred at RT for 30 mins. To the mixture was added asolution of 4-3 (8.5 g, 9.35 mmol) in anhydrous THF (100 mL) at 0° C.,and the reaction mixture was stirred at RT overnight. The reaction wasquenched by water, and extracted with EA (100 mL). The organic layer wasdried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified by silica gel column (DCM/MeOH=100/1 to 20/1) togive 4-4 (4.5 g, 83%) as a white solid.

Compound 4-4 (1.5 g, 2.6 mmol) was co-concentrated with anhydrouspyridine 3 times. To an ice cooled solution of 4-4 in anhydrous pyridine(30 mL) was added TsCl (1.086 g, 5.7 mmol), and the reaction mixture wasstirred at 0° C. for 1 h. The reaction was quenched with water, andextracted with EA (80 mL). The organic layer was dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysilica gel column (DCM/MeOH=100/1 to 15/1) to give 4-5 (1.4 g, 73%) as awhite solid.

To a solution of 4-5 (4.22 g, 5.7 mmol) in acetone (60 mL) was added NaI(3.45 g, 23 mmol), and the mixture was refluxed overnight. The reactionwas quenched by sat. Na₂S₂O₃ aqueous, and then extracted with EA (100mL). The organic layer was dried over anhydrous Na₂SO₄, and concentratedat low pressure. The residue was purified by silica gel column(DCM/MeOH=100/1 to 15/1) to give 4-6 (4 g, 73%) as a white solid.

To a solution of 4-6 (4.0 g, 5.8 mmol) in anhydrous THF (60 mL) wasadded DBU (3.67 g, 24 mmol), and the mixture was stirred at 60° C.overnight. The mixture was diluted with EA (80 mL). The solution waswashed with brine. The organic layer was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The residue was purified by silica gelcolumn (DCM/MeOH=100/1 to 20/1) to give 4-7 (2 g, 61%) as a white solid.

To an ice cooled solution of 4-7 (500 mg, 0.89 mmol) in anhydrous DCM(20 mL) was added AgF (618 mg, 4.9 mmol) and a solution of I₂ (500 mg,1.97 mmol) in anhydrous DCM (20 mL). The mixture was stirred at RT for 3h. The reaction was quenched with sat Na₂S₂O₃ and NaHCO₃ aqueous, andthe mixture was extracted with DCM (50 mL). The organic layer wasseparated, dried over anhydrous Na₂SO₄, and concentrated to give crude4-8 (250 mg, crude) as a yellow solid.

To a solution of crude 4-8 (900 mg, 1.28 mmol) in anhydrous DCM (50 mL)was added DMAP (1.0 g, 8.2 mmol) and BzCl (795 mg, 5.66 mmol). Themixture was stirred at RT overnight. The mixture was washed with sat.NaHCO₃ aq. and brine. The organic layer was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The residue was purified by prep-TLC(DCM/MeOH=15:1) to give 4-9 (300 mg, 26%) as a white solid.

To a solution of crude 4-9 (750 mg, 0.82 mmol) in anhydrous HMPA (20 mL)was added NaOBz (1.2 g, 8.3 mmol) and 15-crown-5 (1.8 g, 8.3 mmol). Themixture was stirred at 60° C. for 2 d. The mixture was diluted with EA,and the solution was washed with brine. The organic layer was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by prep-TLC (PE/EA=1:1) to give crude 4-10 (550 mg, 73%) as awhite solid.

Crude 4-10 (550 mg, 0.6 mmol) was dissolved in NH₃/MeOH (7N, 50 mL). Themixture was stirred at RT overnight. The mixture was concentrated, andthe residue was purified by silica gel column (DCM/MeOH from 100/1 to20/1) to give 4-11 (62 mg, 17%) as white solid. ESI-MS: m/z 598.0[M+H]⁺.

A solution of 4-11 (12 mg) in 80% formic acid (0.5 mL) stood at RT for3.5 h and then was concentrated. The residue was co-evaporated withMeOH/toluene 4 times in a vial, then triturated with EtOAc at 40° C. TheEtOAc solution removed with pippet, and the trituration step wasrepeated several times. The remaining solid was dissolved in MeOH. Thesolution was concentrated and dried to give compound 4 (4.7 mg) as anoff white solid. ESI-MS: m/z 326.6 [M+H]⁺.

Example 4 Compound 5

To a solution of 5-1 (1.2 g; 4.3 mmol) in dioxane (30 mL) were addedp-toluenesulphonic acid monohydrate (820 mg; 1 eq.) and trimethylorthoformate (14 mL; 30 eq.). The mixture was stirred overnight at RT.The mixture was then neutralized with methanolic ammonia and the solventevaporated. Purification on silica gel column with CH₂Cl₂-MeOH solventsystem (4-10% gradient) yielded 5-2 (1.18 g, 87%).

To an ice cooled solution of 5-2 (0.91 g; 2.9 mmol) in anhydrous THF (20mL) was added iso-propylmagnesium chloride (2.1 mL; 2 M in THF). Themixture stirred at 0° C. for 20 mins. A solution of phosphorochloridatereagent (2.2 g; 2.5 eq.) in THF (2 mL) was added dropwise. The mixturestirred overnight at RT. The reaction was quenched with saturated aq.NH₄Cl solution and stirred at RT. for 10 mins. The mixture was thendiluted with water and CH₂Cl₂, and the two layers were separated. Theorganic layer was washed with water, half saturated aq. NaHCO₃ andbrine, and dried with Na₂SO₄. The evaporated residue was purified onsilica gel column with CH₂Cl₂-iPrOH solvent system (4-10% gradient) toyield Rp/Sp-mixture of 5-3 (1.59 g; 93%).

A mixture of 5-3 (1.45 g; 2.45 mmol) and 80% aq. HCOOH (7 mL) wasstirred at RT. for 1.5 h. The solvent was evaporated and coevaporatedwith toluene. The obtained residue was dissolved in MeOH, treated withEt₃N (3 drops) and the solvent was evaporated. Purification on silicagel column with CH₂Cl₂-MeOH solvent system (4-10% gradient) yieldedRp/Sp-mixture of compound 5 (950 mg; 70%). ³¹P-NMR (DMSO-d₆): δ 3.52,3.37. MS: m/z=544 [M−1].

Example 5 Compound 6

Compound 32-1 (5 g, 8.79 mmol) was co-evaporated with anhydrouspyridine. To an ice cooled solution of 32-1 in anhydrous pyridine (15mL) was added TsCl (3.43 g, 17.58 mmol), and stirred for 1 h at 0° C.The reaction was checked by LCMS and TLC. The reaction was quenched withH₂O, and extracted with EA. The organic phase was dried over anhydrousNa₂SO₄, and evaporated at low pressure. Compound 6-1 (6.35 g, 100%) wasused for next step directly.

To a solution of 6-1 (31.77 g, 43.94 mmol) in acetone (300 mL) was addedNaI (65.86 g, 439.4 mmol), and heated to reflux overnight. The reactionwas checked by LCMS. The reaction was quenched with sat. Na₂S₂O₃solution, and extracted with EA. The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (MeOH in DCM from 1% to 6%)to give 6-2 (11.5 g, 38%) as a white solid.

To a solution of 6-2 (11.5 g, 16.94 mmol) in dry THF (120 mL) was addedDBU (12.87 g, 84.68 mmol), and heated to 60° C. The reaction was stirredovernight and checked by LCMS. The reaction was quenched with sat.NaHCO₃ solution, and extracted with EA. The organic phase was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (MeOH in DCM from 1% to 5%)to give 6-3 (5.5 g, 54%) as a white solid.

To an ice cooled solution of 6-3 (500 mg, 0.90 mmol) in dry DCM (20 mL)was added AgF (618 mg, 4.9 mmol) and a solution of I₂ (500 mg, 1.97mmol) in dry DCM (20 mL). The reaction was stirred for 3 h., and checkedby LCMS. The reaction was quenched with sat Na₂S₂O₃ solution and sat.NaHCO₃ solution, and the mixture was extracted with DCM. The organiclayer was dried by anhydrous Na₂SO₄, and evaporated at low pressure togive crude 6-4 (420 mg, 66%).

To a solution of crude 6-4 (250 mg, 0.36 mmol) in dry DCM (8 mL) wasadded DMAP (0.28 g, 2.33 mmol), TEA (145 mg, 1.44 mmol) and BzCl (230mg, 1.62 mmol) in a solution of DCM (2 mL). The reaction was stirredovernight, and checked by LCMS. The mixture was washed with sat. NaHCO₃solution and brine. The organic layer was evaporated at low pressure.The residue was purified by prep-TLC to give crude 6-5 (150 mg, 46%).

To a solution of crude 6-5 (650 mg, 0.72 mmol) in dry HMPA (20 mL) wasadded NaOBz (1.03 g, 7.2 mmol) and 15-crown-5 (1.59 g, 7.2 mmol). Thereaction was stirred for 2 d at 60° C. The mixture was diluted with H₂O,and extracted with EA. The organic layer was evaporated at low pressure.The residue was purified by prep-TLC to give 6-6 (210 mg, 32.4%).ESI-MS: m/z: 900.4 [M+H]⁺.

A mixture of 6-6 (25 mg) and BuNH₂ (0.8 mL) was stirred overnight at RT.The mixture was evaporated and purified on silica gel (10 g column) withCH₂Cl₂/MeOH (4-15% gradient) to yield 6-7 (15 mg, 91%).

A mixture of 6-7 (15 mg, 0.02 mmol) in ACN (0.25 mL) and 4 N HCL/dioxane(19 uL) was stirred at RT for 45 mins. The mixture was diluted with MeOHand evaporated. The crude residue was treated with MeCN, and the solidwas filtered to yield compound 6 (7 mg). MS: m/z=314 [M−1].

Example 6 Compound 7

A mixture of 7-1 (170 mg, 0.19 mmol) and methanolic ammonia (7 N; 3 mL)was stirred at RT for 8 h, concentrated and purified on silica gel (10 gcolumn) with CH₂Cl₂/MeOH (4-11% gradient) to give 7-2 (100 mg, 90%).

Compound 7-2 was rendered anhydrous by co-evaporating with pyridine,followed by toluene. To a solution of 7-2 (24 mg, 0.04 mmol), andN-methylimidazole (17 μL, 5 eq.) in acetonitrile (1 mL) was added thephosphorochloridate (50 mg, 3.5 eq.) in 2 portions in 6 h intervals. Themixture was stirred at RT for 1 d and evaporated. Purification on silica(10 g column) with CH₂Cl₂/MeOH (4-12% gradient) yielded 7-3 (10 mg,28%).

A solution of 7-3 (9 mg, 0.01 mmol) in 80% formic acid was stirred 3 hat RT. The mixture was evaporated and purified on silica (10 g column)with CH₂Cl₂/MeOH (5-15% gradient) to give compound 7 (3 mg, 50%). MS:m/z=624 [M−1].

Example 7 Compound 8

To an ice cooled solution of 8-1 (80 mg; 015 mmol) in anhydrous THF (2mL) was added isopropylmagnesium chloride (0.22 mL; 2 M in THF). Themixture stirred at 0° C. for 20 mins. A solution of thephosphorochloridate reagent (0.16 g; 0.45 mmol) in THF (0.5 mL) wasadded dropwise. The mixture stirred overnight at RT. The reaction wasquenched with saturated aq. NH₄Cl solution and stirred at RT for 10mins. The mixture was diluted with water and CH₂Cl₂, and the two layerswere separated. The organic layer was washed with water, half saturatedaq. NaHCO₃ and brine, and dried with Na₂SO₄. The evaporated residue waspurified on silica gel column with CH₂Cl₂-MeOH solvent system (2-10%gradient) to yield Rp/Sp-mixture of 8-2 (102 mg; 80%).

A mixture of 8-2 (100 mg; 0.12 mmol) in EtOH (3 mL) and 10% Pd/C (10 mg)was stirred under the H₂ atmosphere for 1.5 h. The mixture was filteredthrough a Celite pad, evaporated and purified on silica gel column withCH₂Cl₂-MeOH solvent system (4-10% gradient) to yield Rp/Sp-mixture ofcompound 8 (52 mg, 74%). MS: m/z=584 [M−1].

Example 8 Compound 9

A mixture of 9-1 (1.2 g, 4.3 mmol), PTSA monohydrate (0.82 g, 1 eq.),and trimethyl orthoformate (14 mL, 30 eq.) in dioxane (30 mL) wasstirred overnight at RT. The reaction was neutralized with 7 N NH₃/MeOHand a white solid removed by filtration. The residue was dissolved inTHF (10 mL) and treated with 80% aq. AcOH (5 mL). The mixture was keptat RT for 45 mins and then evaporated. The residue was purified onsilica gel (25 g column) with CH₂Cl₂/MeOH (4-10% gradient) to give 9-2(1.18 g, 87%).

Compound 9-3 (137 mg, 75%) was prepared from 9-2 (93 mg, 0.29 mmol) andtriethylammonium bis(isopropyloxycarbonyloxymethyl)phosphate (0.44 mmol)with DIPEA (0.2 mL), BopCl (147 mg), and 3-nitro-1,2,4-triazole (66 mg)in THF (3 mL). Purification was done with CH₂Cl₂/i-PrOH solvent system(3-10% gradient).

A solution of 9-3 (137 mg) in 80% aq. HCOOH was stirred at RT for 2 h,and then concentrated. The residue was co-evaporated with toluene andthen MeOH containing a small amount of a small amount of Et₃N (2 drops).Purification on silica (25 g column) with CH₂Cl₂/MeOH (4-10% gradient)gave compound 9 (100 mg, 77%). MS: m/z=1175 (2M−1).

Example 9 Compound 10

Compound 10-1 (50 g, 86.0 mmol) and 6-Cl-guanine (16.1 g, 98.2 mmol)were co-evaporated with anhydrous toluene 3 times. To a solution of 10-1in MeCN (200 mL) was added DBU (39.5 g, 258.0 mmol) at 0° C. The mixturewas stirred at 0° C. for 30 mins, and then TMSOTf (95.5 g, 430.0 mmol)was added dropwise at 0° C. The mixture was stirred at 0° C. for 30mins. The mixture was heated to 70° C., and stirred overnight. Thesolution was cooled to RT and diluted with EA (100 mL). The solution waswashed with sat. NaHCO₃ solution and brine. The organic layer was driedover Na₂SO₄, and concentrated at low pressure. The residue was purifiedby column on silica gel (EA in PE from 10% to 40%) to give 10-2 (48.0 g,yield: 88.7%) as a yellow foam. ESI-MS: m/z 628 [M+H]⁺.

To a solution of 10-2 (48.0 g, 76.4 mol), AgNO₃ (50.0 g, 294.1 mmol) andcollidine (40 mL) in anhydrous DCM (200 mL) was added MMTrCl (46.0 g,149.2 mmol) in small portions under N₂. The mixture was stirred at RTfor 3 h under N₂. The reaction was monitored by TLC. The mixture wasfiltered, and the filter was washed with sat. NaHCO₃ solution and brine.The organic layer was dried over anhydrous Na₂SO₄, and concentrated atlow pressure. The residue was purified by silica gel column (EA in PEfrom 5% to 50%) to the give crude 10-3 (68 g, 98%). ESI-MS: m/z 900.1[M+H]⁺.

Sodium (8.7 g, 378.0 mmol) was dissolved in dry EtOH (100 mL) at 0° C.,and slowly warmed to RT. Compound 10-3 (68.0 g, 75.6 mmol) was treatedwith freshly prepared NaOEt solution, and stirred overnight at RT. Thereaction was monitored by TLC, and the mixture was concentrated at lowpressure. The mixture was diluted with H₂O (100 mL), and extracted withEA (3×100 mL). The organic layer was dried over anhydrous Na₂SO₄, andevaporated at low pressure. The residue was purified by silica gelcolumn chromatography (MeOH in DCM from 1% to 5%) to give 10-4 (34.0 g,75.2%) as a yellow solid. ESI-MS: m/z 598 [M+H]⁺.

Compound 10-4 (32.0 g, 53.5 mmol) was co-evaporated with anhydrouspyridine 3 times. To an ice cooled solution of 10-4 in anhydrouspyridine (100 mL) was added TsCl (11.2 g, 58.9 mmol) in pyridine (50 mL)dropwise at 0° C. The mixture was stirred for 18 h. at 0° C. Thereaction was checked by LCMS (about 70% was the desired product). Thereaction was quenched with H₂O, and the solution was concentrated at lowpressure. The residue was dissolved in EA (100 mL), and washed with sat.NaHCO₃ solution. The organic layer was dried over anhydrous Na₂SO₄, andevaporated at low pressure. The residue was purified by silica gelcolumn chromatography (MeOH in DCM from 1% to 5%) to give crude 10-5(25.0 g, 62.2%) as a yellow solid. ESI-MS: m/z 752 [M+H]⁺.

To a solution of 10-5 (23.0 g, 30.6 mmol) in acetone (150 mL) was addedNaI (45.9 g, 306.0 mmol) and TBAI (2.0 g), and refluxed overnight. Thereaction was monitored by LCMS. After the reaction was complete, themixture was concentrated at low pressure. The residue was dissolved inEA (100 mL), washed with brine, and dried over anhydrous Na₂SO₄. Theorganic solution was evaporated at low pressure. The residue waspurified by silica gel column chromatography (DCM: MeOH=100:1 to 20:1)to give the crude product. To a solution of the crude product in dry THF(200 mL) was added DBU (14.0 g, 91.8 mmol), and heated to 60° C. Themixture was stirred overnight, and checked by LCMS. The reaction wasquenched with sat. NaHCO₃, and the solution was extracted with EA (100mL). The organic layer was dried over anhydrous Na₂SO₄, and evaporatedat low pressure. The residue was purified by silica gel columnchromatography (MeOH in DCM from 1% to 5%) to give 10-6 (12.0 g, 67.4%)as a yellow solid. ESI-MS: m/z 580 [M+H]⁺.

To an ice cooled solution of 10-6 (8.0 g, 13.8 mmol) in dry MeCN (100mL) was added NIS (3.9 g, 17.2 mmol) and TEA.3HF (3.3 g, 20.7 mmol) at0° C. The mixture was stirred at RT for 18 h and checked by LCMS. Afterthe reaction was complete, the reaction was quenched with sat Na₂SO₃ andsat. NaHCO₃ solution. The solution was extracted with EA. The organiclayer was dried over anhydrous Na₂SO₄, and evaporated at low pressure.The residue was purified by silica gel column chromatography (EA in PEfrom 10% to 50%) to give 10-7 (7.2 g, 72.0%) as a solid. ESI-MS: m/z 726[M+H]⁺.

To a solution of crude 10-7 (7.2 g, 9.9 mmol) in dry DCM (100 mL) wasadded DMAP (3.6 g, 29.8 mmol), and BzCl (2.8 g, 19.8 mmol) at 0° C. Themixture was stirred overnight, and checked by LCMS. The mixture waswashed with sat. NaHCO₃ solution. The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (EA in PE from 10% to 30%)to give 10-8 (8.0 g, 86.4%) as a solid. ESI-MS: m/z 934 [M+H]⁺.

To a solution of 10-8 (7.5 g, 8.0 mmol) in dry DMF (100 mL) was addedNaOBz (11.5 g, 80.0 mmol) and 15-crown-5 (15.6 mL). The mixture wasstirred for 36 h. at 90° C. The mixture was diluted with H₂O (100 mL),and extracted with EA (3×150 mL). The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (EA in PE from 10% to 30%)to give crude 10-9 (6.0 g, 80.0%) as a solid. ESI-MS: m/z 928 [M+H]⁺.

Compound 10-9 (4.0 g, 4.3 mmol) was co-evaporated with anhydrous toluene3 times, and treated with NH₃/MeOH (50 mL, 4N) at RT. The mixture wasstirred for 18 h at RT. The reaction was monitored by LCMS, and themixture was concentrated at low pressure. The residue was purified bysilica gel column chromatography (EA in PE from 30% to 50%) to give10-10 (1.9 g, 71.7%) as a solid. ESI-MS: m/z 616 [M+H]⁺.

Compound 10-10 (300.0 mg, 0.49 mmol) was co-evaporated with anhydroustoluene 3 times, and was dissolved in MeCN (2 mL). The mixture wastreated with NMI (120.5 mg, 1.47 mmol) and the phosphorochloridatereagent (338.1 mg, 0.98 mmol) in MeCN (1 mL) at 0° C. The mixture wasstirred for 18 h at RT. The reaction was monitored by LCMS. The mixturewas diluted with 10% NaHCO₃ solution, and extracted with EA. The residuewas purified by silica gel column chromatography (EA in PE from 30% to50%) to give 10-11 (240 mg, 53.3%) as a solid. ESI-MS: m/z 925 [M+H]⁺.

Compound 10-11 (240.0 mg, 0.26 mmol) was treated with 80% AcOH (10 mL),and the mixture was stirred for 18 h at RT. The reaction was monitoredby LCMS. The mixture was concentrated at low pressure. The residue waspurified by silica gel column chromatography (MeOH in DCM from 1% to 3%)to give compound 10 (87.6 mg, 51.7%) as a solid. ESI-MS: m/z 653 [M+H]⁺.

Example 10 Compound 12

To a stirred suspension of 12-1 (20.0 g, 81.3 mmol), imidazole (15.9 g,234.0 mmol), PPh₃ (53.5 g, 203.3 mmol) and pyridine (90 mL) in anhydrousTHF (100 mL) was added a solution of I₂ (41.3 g, 162.6 mmol) in THF (150mL) dropwise at 0° C. The mixture was slowly warmed to RT and stirredfor 14 h. The reaction was quenched with sat. aq. Na₂S₂O₃ (150 mL) andextracted with THF/EA (1/1) (100 mL×3). The organic layer was dried overNa₂SO₄, and concentrated at a low pressure. The residue wasrecrystallized from EtOH to afford pure 12-2 (23 g, 79%) as a whitesolid.

To a stirred solution of 12-2 (23 g, 65 mmol) in anhydrous MeOH (200 mL)was added NaOCH₃ (10.5 g, 195 mmol) in MeOH (50 mL) at RT. The mixturewas stirred at 60° C. for 3 h, and quenched with dry ice. A solidprecipitated and removed by filtration. The filtrate was concentrated ata low pressure. The residue was purified on column silica gel column(MeOH in DCM from 1% to 10%) to provide 12-3 (13.1 g, 92.5%) as a whitefoam solid.

To a stirred solution of 12-3 (12.0 g, 53 mmol) in anhydrous CH₃CN wasadded TEA.3HF (8.5 g, 53 mmol) and NIS (10.2 g, 63.6 mmol) at 0° C. Themixture was stirred for 30 mins, and slowly warmed to RT. The mixturewas stirred for another 30 mins. The solid was removed by filtration,and washed with DCM to give 12-4 (14 g, 73%) as a yellow solid. ESI-MS:m/z 373.0 [M+H]⁺.

To a stirred solution of 12-4 (12.0 g, 32 mmol) and DMAP (1.2 g, 9.6mmol) in pyridine (100 mL) was added Bz₂O (21.7 g, 96 mmol) at RT. Themixture was stirred at 50° C. for 16 h. The resulting solution wasquenched with water, and concentrated to dryness at low pressure. Thecrude was purified on silica gel column (50% EA in PE) to give 12-5 (15g, 81%) as a white solid. ESI-TOF-MS: m/z 581.0 [M+H]⁺.

Tetra-butylammonium hydroxide (288 mL as 54-56% aqueous solution, 576mmol) was adjusted to pH˜4 by adding TFA (48 mL). The resulting solutionwas treated with a solution of 12-5 (14 g, 24 mmol) in DCM (200 mL).m-Chloroperbenzoic acid (30 g, 60-70%, 120 mmol) was added portion wisewith vigorous stirring, and the mixture was stirred overnight. Theorganic layer was separated and washed with brine. The resultingsolution was dried over magnesium sulfate and concentrated under reducedpressure. The residue was purified by column chromatography to give 12-6(7.5 g, 68%)

Compound 12-6 (5.0 g, 10.6 mmol) was treated with 7N NH₃.MeOH (100 mL),and the mixture was stirred for 5 h. The mixture was then concentratedto dryness at low pressure. The residue was washed with DCM, and thesolid was filtered to give 12-7 (2.1 g, 75%) as a white foam. ESI-MS:m/z 263.0 [M+H]⁺.

To a solution of 12-7 (2.1 g, 8.0 mmol) in pyridine was added TIDPSCl(2.5 g, 8.0 mmol) dropwise at 0° C., and stirred for 12 h. at RT. Thesolution was quenched with water, and concentrated to dryness at lowpressure. The crude was purified by column chromatography (EA in PE from10% to 50%) to give pure 12-8 (1.6 g, 40%) as a white foam.

A solution of 12-8 (1.5 g, 3.0 mmol) and IBX (1.69 g, 6.0 mmol) inanhydrous CH₃CN (10 mL) was stirred at 80° C. for 3 h. The mixture wascooled down to RT and filtered. The filtrate was concentrated to drynessat low pressure. The residue was purified by column chromatography (EAin PE from 2% to 50%) to give pure 12-9 (1.2 g, 80%) as a white foam.ESI-MS: m/z 503.0 [M+H]⁺

Compound 12-9 (500 mg, 1 mmol) was dissolved in dry THF (8 mL). Ethynylmagnesium bromide (8 mL of 0.5M solution in cyclohexane) was added atRT. After 30 mins, additional ethynyl magnesium bromide (8 mL) wasadded. The mixture was left for 30 mins, and then quenched with sat.solution of ammonium chloride. The product was extracted with EA. Theorganic extracts were washed with brine, dried, and concentrated. Theresidue was purified by flash chromatography on silica gel in EA toremove the dark color. The yellow compound was dissolved in THF (3 mL)and treated with TBAF (1 mL, 2M solution in THF) for 30 mins. Thesolvent was evaporated, and the residue was subjected to silica gelchromatography on a Biotage cartridge (25 g). EA saturated with waterwas used for isocratic elution. Each fraction was analyzed by TLC inDCM:MeOH (9:1 v:v). Fractions containing only the isomer with a high Rfwere concentrated to give pure compound 12 (110 mg). MS: 285.1 [M−1].

Example 11 Compound 13

Compound 12 (57 mg, 0.2 mmol) was dissolved in CH₃CN (2 mL), containingN-methylimidazole (40 uL). The phosphorochloridate reagent (207 mg, 0.6mmol) was added, and the mixture was kept overnight at 40° C. Themixture was distributed between water and EA. The organic layer wasseparated, washed with brine, dried and evaporated. The product wasisolated by silica gel chromatography in gradient of methanol in DCMfrom 0% to 15%. Compound 13 was obtained (46 mg, 39%). MS: m/z 593.9[M−1].

Example 12 Compound 14

To a stirred solution of 14-1 (5.0 g, 19.53 mmol) in anhydrous MeCN wasadded IBX (7.66 g, 27.34 mmol) at RT. The mixture was heated at 80° C.for 12 h, and then slowly cooled to RT. After filtration, the filtratewas concentrated to give crude 14-2 (4.87 g, 98%).

To a solution of 14-2 (4.96 g, 19.53 mmol) in anhydrous THF at −78° C.under N₂ was added methyl magnesium bromide (19.53 mL, 58.59 mmol) bydropwise. The mixture was slowly warmed to RT, and stirred for 12 h. Themixture was quenched with sat. NH₄Cl solution, and extracted with EA.The organic layer was dried over anhydrous Na₂SO₄, and evaporated at lowpressure. The residue was purified by silica gel column chromatographyto give 14-3 (4.37 g, 83%) as a white solid.

To a solution of 14-3 (4.37 g, 16.19 mmol) in anhydrous DCM (20 mL) wasadded DMAP (3.95 g, 32.38 mmol), TEA (4.91 g, 48.56 mmol), and BzCl(6.80 g, 48.56 mmol) at 0° C. The mixture was stirred at RT overnight.The reaction was quenched with sat. NaHCO₃ solution (30 mL), andextracted with EA (3×50 mL). The organic layer was dried over anhydrousNa₂SO₄, and evaporated at low pressure. The residue was purified bysilica gel column chromatography to give crude 14-4 (5.3 g, 87%) as awhite solid.

To a solution of 14-4 (3.0 g, 8.02 mmol) and Ac₂O (4.91 g, 48.13 mmol)in acetic acid (10 mL) was added concentrated H₂SO₄ (98%, 2.41 g, 24.06mmol) at 0° C. The mixture was stirred at RT for 12 h. The solution waspoured into ice water (30 mL), and extracted with EA (3×50 mL). Theorganic layer was dried over anhydrous Na₂SO₄, and evaporated at lowpressure. The residue was purified by silica gel column chromatographyto give 14-5 (2.3 g, 81%)) as a white solid.

To a stirred solution of 6-Cl-guanine (560 mg, 3.31 mmol) and 14-5 (1.11g, 2.76 mmol) in anhydrous MeCN (5 mL) was added DBU (1.27 g, 8.28 mmol)under N₂ at 0° C. The mixture was stirred at RT for 30 mins. The mixturewas cooled to 0° C., and TMSOTf (2.45 g, 11.04 mmol) was added slowly in15 mins. The mixture was then warmed RT in 30 mins. The mixture washeated at 60° C. for 4 h. The mixture was then poured into ice water (30mL), and extracted with EA (3×50 mL). The organic layer was dried overanhydrous Na₂SO₄ and evaporated at low pressure. The residue waspurified by silica gel column chromatography to give 14-6 (800 mg, 70%)as a white solid.

To a solution of 14-6 (839 mg, 1.64 mmol), MMTrCl (1.46 g, 4.75 mmol)and AgNO₃ (697 mg, 4.1 mmol) in DCM (10 mL) was added collidine (794 mg,6.56 mmol). The mixture was stirred for 12 h at RT. The reaction wasquenched with sat. NaHCO₃ solution (20 mL). After filtration, thefiltrate was extracted with DCM (3×20 mL). The organic layer was driedover anhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography to give 14-7 (1.3 g, 72.5%)as a white solid.

3-hydroxyl acrylic nitrile (4.13 g, 5.82 mmol) was dissolved inanhydrous THF (10 mL). The solution was treated with NaH (464 mg, 11.6mmol) at 0° C., and slowly warmed to RT, and stirred for 30 mins. Asolution of 14-7 (912 mg, 1.16 mmol) in anhydrous THF (5 mL) was addedslowly. The mixture was stirred at RT overnight. The reaction wasquenched with water (40 mL), and extracted with EA (3×50 mL). Theorganic layer was dried over anhydrous Na₂SO₄, and evaporated at lowpressure. The residue was purified by silica gel column chromatographyto give 14-8 (600 mg, 85%) as a white solid.

To a solution of 14-8 (6.20 g, 10.86 mmol) in anhydrous pyridine (10 mL)at 0° C. was added a solution of TsCl (4.54 g, 23.89 mmol) in anhydrouspyridine (10 mL) dropwise. The mixture was stirred at RT for 30 mins.The mixture was quenched with water (30 mL), and extracted with EA (3×50mL). The organic layer was dried over anhydrous Na₂SO₄, and evaporatedat low pressure. The residue was purified by silica gel columnchromatography to give 14-9 (6.0 g, 76%) as a white solid.

To a solution of 14-9 (6.0 g, 8.28 mmol) in acetone (30 mL) was NaI(4.97 g, 33.12 mmol), and refluxed overnight. The mixture was evaporatedunder reduced pressure. The residue was dissolved in EA (50 mL), andwashed with sat. NaHCO₃ solution (30 mL). The organic layer was driedover anhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography to give 14-10 (5.43 g,96.4%) as a white solid.

To a solution of 14-10 (5.0 g, 7.34 mmol) in anhydrous THF (20 mL) wasadded DBU (4.49 g, 29.37 mmol), and stirred at 60° C. overnight. Themixture was slowly cooled to RT. The mixture was quenched with water (30mL), and extracted with EA (3×50 mL). The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography to give 14-11 (3.5 g, 85%)as a white solid.

To a solution of 14-11 (3.5 g, 6.33 mmol) and AgF (4.42 g, 34.81 mmol)in anhydrous DCM (20 mL) was added a solution of iodine (3.54 g, 13.93mmol) in anhydrous DCM (5 mL) dropwise at 0° C. The mixture was stirredfor 3 h. The reaction mixture was washed with sat. NaHCO₃ solution (40mL) and extracted with EA (3×50 mL). The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography to give crude 14-12 (1.37g, 31%) as a white solid.

To a solution of 14-12 (1.37 g, 1.96 mmol) in anhydrous DMF (15 mL) wasadded sodium benzoate (2.82 g, 19.60 mmol) and 15-crown-5 (4.31 g, 19.60mmol), and stirred at 90° C. for 3 d. The mixture was quenched withwater (30 mL), and extracted with EA (3×50 mL). The organic layer wasdried over anhydrous Na₂SO₄, and evaporated at low pressure. The residuewas purified by HPLC separation to give 14-13 (250 mg, 20%). ESI-MS:m/z: 694 [M+H]⁺

A mixture of 14-13 (250 mg, 0.36 mmol) in liquid ammonia was keptovernight at RT in high pressure glass vessel. Ammonia was thenevaporated, and the residue purified on silica gel (10 g column) withCH₂Cl₂/MeOH (4-10% gradient) to give 14-14 (180 mg, 85%).

Compound 14 (85 mg, 56%) was prepared from 14-14 (99 mg) with i-PrMgCl(0.11 mL) and the phosphorochloridate reagent (94 mg) in THF (2 mL)followed by deprotection. MS: m/z=627 [M+1].

Example 13 Compound 15

To a solution of 15-1 (260 mg, 1 mmol), PPh₃ (780 mg, 3 mmol) andpyridine (0.5 mL) in anhydrous THF (8 mL) were added I₂ (504 mg, 2 mmol)at RT, and the mixture was stirred at RT for 12 h. The mixture wasdiluted with EtOAc and washed with 1M HCl solution. The organic layerwas dried over Na₂SO₄, filtered and concentrated at low pressure. Theresidue was purified by silica gel column (5% MeOH in DCM) to give 15-2(190 mg, 85%) as a white solid.

To a solution of 15-2 (190 mg, 0.52 mmol) in THF (4 mL) was added DBU(760 mg, 5 mmol) at RT, and the mixture was heated at 50° C. overnight.The mixture was diluted with EtOAc, and washed with water. The organiclayer was dried over anhydrous Na₂SO₄ and concentrated at low pressure.The residue was purified by silica gel column (30% EA in PE) to give15-3 (75 mg, 52%) as a white solid.

To a solution of 15-3 (200 mg, 0.82 mmol) in MeCN (anhydrous, 4 mL) wasadded NIS (337 mg, 1.5 mmol) and TEA.3HF (213 mg, 1.25 mmol) at RT, andthe mixture was stirred at RT for 7 h. The reaction was quenched withsat. Na₂SO₃ solution and sat. aq. NaHCO₃ solution. The mixture wasextracted with EA. The organic layer was separated, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysilica gel column (20% EA in PE) to give 15-4 (300 mg, 62%) as a whitesolid.

To a solution of 15-4 (194 mg, 0.5 mmol) in pyridine (5 mL) was addedBzCl (92 mg, 0.55 mmol) at 0° C. The mixture was stirred at RT for 5 h,and the reaction was quenched with water. The mixture was concentratedat low pressure, and the residue was purified by silica gel column (20%EA in PE) to give 15-5 (397 mg, 81%) as a white solid.

To a solution of 15-5 (1.05 g, 2.13 mmol) in DCM (12 mL) was added amixture of TFA (0.5 mL) and Bu₄NOH (1 mL), followed by addition ofm-CPBA (1.3 g, 6 mmol) at RT. The mixture was stirred at RT for 5 h. Themixture was washed with sat. Na₂SO₃ solution and aq. NaHCO₃ solution.The organic layer was dried over anhydrous Na₂SO₄, and concentrated atlow pressure. The residue was purified by silica gel column (30% EA inPE) to give 15-6 (450 mg, 63%) as a white solid.

Compound 15-6 (250 mg, 0.65 mmol) was dissolved in NH₃/MeOH (5 mL). Themixture was stirred at RT for 5 h, and then concentrated at lowpressure. The residue was purified by silica gel column (5% MeOH in DCM)to give compound 15 (120 mg, 66%) as a white powder. ESI-MS: m/z 279.0[M+H]⁺.

Example 14 Compound 16

Sodium (6.0 g, 261.2 mmol) was dissolved in dry EtOH (400 mL) at 0° C.,and slowly warmed to RT. Compound 14-7 (32.0 g, 43.5 mmol) was treatedwith a freshly prepared NaOEt solution at 0° C., and the mixture wasstirred at RT overnight. The reaction was monitored by TLC and LCMS.After completion of the reaction, the mixture was concentrated at lowpressure. The mixture was quenched with H₂O (40 mL), and extracted withEA (3×50 mL). The organic layer was dried over anhydrous Na₂SO₄, andevaporated at low pressure. The residue was purified by silica gelcolumn chromatography (MeOH in DCM from 0.5% to 2%) to give 16-1 (20.0g, 76.6%) as a white solid.

Compound 16-1 (20.0 g, 33.3 mmol) was co-evaporated with anhydrouspyridine 3 times. To an ice cooled solution of 16-1 in anhydrouspyridine (100 mL) was added TsCl (9.5 g, 49.9 mmol) at 0° C. Afteraddition, the reaction was stirred for 12 h at 20° C., and monitored byLCMS. The reaction was quenched with H₂O, and concentrated at lowpressure. The residue was dissolved in EA (50 mL). The solution waswashed with sat. NaHCO₃ solution and brine. The organic layer was driedover anhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (MeOH in DCM from 0.5% to2%) to give 16-2 (20.0 g, 80%) as a yellow solid.

To a solution of 16-2 (20.0 g, 26.5 mmol) in acetone (100 mL) was addedNaI (31.8 g, 212 mmol), and heated to reflux overnight. The reaction waschecked by LCMS. After the reaction was complete, the mixture wasconcentrated at low pressure. The residue was dissolved in EA (50 mL).The solution was washed with brine. The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (MeOH in DCM from 0.5% to2%) to give a crude product. To a solution of the crude product in dryTHF (60 mL) was added DBU (16.2 g, 106 mmol), and heated to 60° C. Themixture was stirred overnight and checked by LCMS. The reaction wasquenched with sat. NaHCO₃ solution, and extracted with EA (3×50 mL). Theorganic phase was washed with brine, dried over anhydrous Na₂SO₄, andevaporated at low pressure. The residue was purified by silica gelcolumn chromatography (MeOH in DCM from 0.5% to 2%) to give 16-3 (12.0g, 77.9%) as a yellow solid.

To an ice-clod solution of 16-3 (11.0 g, 18.9 mmol) in dry MeCN (100 mL)was added NIS (5.4 g, 23.7 mmol) and NEt₃.3HF (3.0 g, 18.9 mmol) at 0°C. The mixture was stirred at RT for 4 h., and checked by LCMS. Afterthe reaction was complete, the reaction was quenched with sat. Na₂SO₃solution and sat. NaHCO₃ solution. The solution was extracted with EA(3×100 mL). The organic layer was washed with brine, dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (EA in PE from 12% to 50%)to give 16-4 (11.0 g, 79.9%).

To a solution of 16-4 (10.0 g, 13.7 mmol) in dry DMF (100 mL) was addedNaOBz (19.8 g, 137 mmol) and 15-crown-5 (30.2 g, 137 mmol). The reactionwas stirred for 48 h at 90° C., and diluted with EA. The solution waswashed with water and brine, and dried over MgSO₄. The organic layer wasevaporated at low pressure, and the residue was purified by silica gelcolumn chromatography (EA in PE from 12% to 50%) to give 16-5 (8.0 g,80.0%).

Compound 16-5 (6.0 g, 8.3 mmol) was co-evaporated with anhydrous toluene3 times, and treated with NH₃ in MeOH (4N, 50 mL) at RT. The reactionwas stirred for 18 h at RT. The reaction was monitored by LCMS. Afterthe reaction was complete, the mixture was concentrated at low pressure.The residue was purified by silica gel column chromatography (EA in PEfrom 20% to 50%) to give 16-6 (4.5 g, 87.8%). ESI-MS: m/z 617.9 [M+H]⁺.

To an ice cooled mixture of 16-6 (25 mg, 0.07 mmol) and NMI (46 μL, 8eq.) in acetonitrile (0.7 mL) was added the phosphorochloridate reagent(73 mg, 3 eq.) and stirred overnight at RT. Additional amounts of NMI(46 uL) and the phosphorochloridate reagent (73 mg) were added andstirring continued for 1 d. The reaction was quenched with sat. aq.NH₄Cl, diluted with EtOAc and water. The organic layer was separated andwashed with aq. NaHCO₃, water, and brine, and then dried (Na₂SO₄). Theresidue was purified on silica gel (10 g column) with CH₂Cl₂/i-PrOH(4-10% gradient) to yield compound 16 (18 mg, 40%). MS: m/z=655 [M+1].

Example 15 Compound 18

To a solution of compound 15 (139 mg, 0.5 mmol) in pyridine (5 mL) wasadded BzCl (92 mg, 0.55 mmol) at 0° C. The mixture was stirred at RT for5 h, diluted with EtOAc and washed with 1N HCl solution. The organiclayer was dried over anhydrous Na₂SO₄, and concentrated at low pressure.The residue was purified by silica gel column (20% EA in PE) to give18-1 (274 mg, 79%) as a white solid.

To a solution of 18-1 (490 mg, 1 mmol), DMAP (244 mg, 2 mmol) and TEA(205 mg, 2.1 mmol) in MeCN (10 mL) were added TPSCl (604 mg, 2 mmol) at0° C. The mixture was stirred at RT for 2 h., and then NH₄OH aq. wasadded at RT. The mixture was stirred for 0.5 h, diluted with EtOAc andwashed with sat. aq. NaHCO₃ and brine. The organic layer was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by silica gel column (30% EA in PE) to give 18-2 (250 mg, 41%)as a white solid.

Compound 18-2 (250 mg, 0.51 mmol) was dissolved in NH₃/MeOH (15 mL). Themixture was stirred at RT for 5 h. and then concentrated at lowpressure. The residue was purified by silica gel column (5% DCM in DCM)to give compound 18 (95 mg, 66%) as a white powder. ESI-MS: m/z 278.1[M+H]⁺.

Example 16 Compound 20

To a solution of compound 20-1 (30 g, 0.08 mol) in anhydrous THF (300mL) was added a solution of lithium tri-tert-butoxyaluminohydride (120mL, 0.12 mol) dropwise at −78° C. under N₂. The mixture was stirred at−20° C. for 1 h. The reaction was quenched with sat. aq. NH₄Cl and thenfiltered. The filtrate was extracted with EA (3×300 mL). The organiclayer was dried over anhydrous Na₂SO₄, and concentrated at low pressure.The residue was purified by silica gel column (10% EA in PE) to give20-2 (26 g, 86%) as a colorless oil.

To a stirred solution of PPh₃ (37.7 g, 0.144 mol) in DCM (100 mL) wasadded compound 20-2 (27 g, 0.072 mol) at −20° C. under N₂. After themixture was stirred at RT for 15 mins, CBr₄ (42 g, 0.129 mol) was addedwhile maintaining the reaction temperature between −25 and −20° C. underN₂. The mixture was then stirred below −17° C. for 20 mins. Silica gelwas added into the solution, and then purified by flash silica gelcolumn separation to give the crude oil product. The crude was purifiedby silica gel column (EA in PE from 2% to 20%) to give 20-3 (α-isomer,17 g, 55%) as a colorless oil.

A mixture of 6-Cl-guanine (11.6 g, 68.8 mmol) and t-BuOK (8.2 g, 73mmol) in t-BuOH (200 mL) and MeCN (150 mL) was stirred at 35° C. for 30mins, and then 20-3 (10 g, 22.9 mmol) in MeCN 100 mL) was added at RT.The mixture was heated at 50° C. overnight. The reaction was quenchedwith a solution of NH₄Cl (5 g) in water (40 mL), and the mixture wasfiltered. The filtrate was evaporated at low pressure. The residue waspurified by silica gel column (20% EA in PE) to give 20-4 (6 g, 42%) asa yellow solid.

To a solution of 20-4 (12.5 g, 23.8 mol) in DCM (50 mL) was added AgNO₃(8.1 g, 47.6 mmol), collidine (5.77 g, 47.6 mmol) and MMTrCl (11 g, 35.7mmol). The mixture was stirred at RT overnight. The reaction wasquenched with MeOH (5 mL), filtered and concentrated at low pressure.The residue was purified by silica gel column (5% MeOH in DCM) to givethe intermediate (16 g, 86%) as a yellow solid. To a solution ofHOCH₂CH₂CN (4.7 g, 66 mmol) in THF (200 mL) was added NaH (3.7 g, 92mmol) at 0° C. The mixture was stirred at RT for 30 mins. A solution ofthe intermediate (10.5 g, 13 mmol) in THF (50 mL) was added, and thereaction mixture was stirred at RT for 12 h. The reaction was quenchedwith MeOH (2 mL), diluted with EA (100 mL), and washed with brine. Theorganic layer was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel column (5% MeOH in DCM)to give 20-5 (5.8 g, 77%) as a yellow solid.

To a solution of PPh₃ (7.0 g, 26.6 mmol) in anhydrous pyridine (100 mL)was added I₂ (6.3 g, 24.9 mmol), and stirred at RT for 30 mins. Themixture was treated with a solution of 20-5 (9.5 g, 16.6 mmol) inpyridine (40 mL). The mixture was stirred at RT overnight. The reactionwas quenched with sat. Na₂S₂O₃ solution, and the mixture was extractedwith EA. The organic layer was washed with brine, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysilica gel column (30% EA in PE) to give 20-6 (7 g, 66%) as a yellowsolid.

To a solution of 20-6 (7.5 g, 11 mmol) in dry THF (50 mL) was added DBU(5.4 g, 33 mmol), and the mixture was heated to reflux for 4 h. Themixture was diluted with EA (3×100 mL), and washed with brine. Theorganic layer was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel column (30% EA in PE)to give 20-7 (4.0 g, 67%) as a white solid.

To an ice-cooled solution of 20-7 (3.0 g, 5.4 mmol) in anhydrous MeCN(20 mL) was added TEA.3HF (0.65 g, 4.1 mmol) and NIS (1.53 g, 6.78 mmol)at RT, and the reaction mixture was stirred at RT for 2 h. The mixturewas diluted with EA (50 mL), and washed with sat. Na₂S₂O₃ solution andNaHCO₃ aq. The organic layer was dried over anhydrous Na₂SO₄, andconcentrated to dryness at low pressure. The residue was purified byprep-HPLC (0.1% HCOOH in water and MeCN) to separate the two isomers(about 1:1). NOE showed the polar one was 20-8 (0.6 g, 16%) as a whitesolid.

To a solution of 20-8 (0.7 g, 1 mmol) in dry pyridine (10 mL) was addedBzCl (147 mg, 1.05 mmol) at 0° C. The mixture was stirred at RT for 3 h.The mixture was then diluted with EA, and washed with sat. NaHCO₃ aq.and brine. The organic layer was dried over Na₂SO₄, and evaporated atlow pressure. The residue was purified by silica gel column (20% EA inPE) to give 20-9 (0.65 g, 81%) as a white solid.

To a solution of 20-9 (0.65 g, 0.8 mmol) in dry DMF (40 mL) was addedNaOBz (1.15 g, 8 mmol) and 15-crown-5 (1.77 g, 8 mmol). The mixture wasstirred at 100° C. for 48 h. The solvent was evaporated at low pressure,and the residue was dissolved in EA (30 mL), and washed with water andbrine. The organic layer was dried over Na₂SO₄ and concentrated at lowpressure. The residue was purified by silica gel column (20% EA in PE)to give 20-10 (500 mg, 78%) as a white solid.

Compound 20-10 (400 mg, 0.5 mmol) in NH₃/MeOH (7N, 100 mL) was stirredat RT for 18 h. The mixture was concentrated at low pressure, and theresidue was purified by silica gel column (5% MeOH in DCM) to give 20-11(220 mg, 63%) as a white solid. ESI-MS: m/z 590.3 [M+H]⁺.

Compound 20-11 (59 mg, 0.1 mmol) was dissolved in 50% TFA in methanol(10 mL), and the mixture was kept at RT for 2 h. The solvent wasevaporated and co-evaporated with a methanol/toluene mixture to removetraces of the acid. The residue was suspended in CH₃CN (1 mL) andcentrifuged. The precipitate was washed with CH₃CN (1 mL) and dried.Compound 20 was obtained as a colorless solid (21 mg, 65%. MS: m/z 316.2[M−1].

Example 17 Compound 21

Compound 21 (15 mg, 16%) was prepared from 21-1 (50 mg) in acetonitrile(2 mL) with the phosphorochloridate reagent (0.14 g) and NMI (0.1 mL) inthe same manner as compound 7. MS: m/z=643 [M+1].

Example 18 Compound 22

Compound 22 (30 mg, 32%) was prepared from 22-1 (50 mg) in acetonitrile(2 mL) with the phosphorochloridate reagent (0.14 g) and NMI (0.1 mL) inthe same manner as compound 7. MS: m/z=615 [M+1].

Example 19 Compound 23

To a stirred solution of compound 15 (60 mg, 0.22 mmol) in anhydrous THF(2.0 mL) was added N-methylimidazole (0.142 mL, 1.73 mmol) at 0° C. (dryice/acetone bath) followed by solution ofphenyl(cyclohexanoxy-L-alaninyl)phosphorochloridate (235 mg, 0.68 mmol,dissolved in THF (2 mL). The resulting solution was stirred at 0° C. for1 h, and the temperature was raised up-to 10° C. over the next 1 h. Thereaction left at 10° C. for 3 h. The mixture was cooled to 0 to 5° C.,diluted with EA, and water (5 mL) was added. The solution was washedwith H₂O and brine. The organic layer was separated, dried overanhydrous Na₂SO₄ and filtered. The filtrate was concentrated in vacuumto give a residue, which dissolved in 25% CH₃CN/H₂O. The compound waspurified on a reverse-phase HPLC (C18) using acetonitrile and water,followed by lyophilization gave a white foam. The produce wasre-dissolved in EtOAc, washed with 50% aqueous citric acid solution,dried over anhydrous MgSO₄ and filtered. The filtrate was concentratedin vacuum, and lyophilized to give two isomers (Rp/Sp) of compound 23(6.3 mg). MS m/z 586.05 (M−H).

Example 20 Compound 24

To a stirred solution of compound 15 (100 mg, 0.36 mmol) in anhydrousTHF (3.0 mL) was added N-methylimidazole (236 μL, 2.87 mmol) at 0° C.(dry ice/acetone bath) followed by a solution of the phosphorochloridate(329 mg, 1.08 mmol, dissolved in 2 mL of THF). The solution was stirredat 0° C. for 1 h, the reaction temperature was raised up-to 10° C.during the next 1 h, and the solution was left at 10° C. for the next 4h. The mixture was cooled to 0 to 5° C., diluted with EA, and water wasadded (15 mL). The solution was washed H₂O, 50% aqueous citric acidsolution and brine. The organic layer was separated, dried overanhydrous MgSO₄ and filtered. The filtrate was concentrated in vacuum togive a residue, which dissolved in 25% CH₃CN/H₂O. The residue waspurified on a reverse-phase HPLC (C18) using acetonitrile and water,followed by lyophilization to give a mixture of two isomers of compound24 (17.5 mg). MS m/z 546.05 (M−H).

Example 21 Compounds 25 and 26

To a solution of 25-1 (0.47 g, 0.65 mol) in DCM (3 mL) was added AgNO₃(0.22 g, 1.29 mmol), collidine (0.15 g, 1.29 mmol) and MMTrCl (0.3 g,0.974 mmol) at 0° C. The mixture was stirred at RT overnight. Themixture was filtered, and the filter was washed with sat. aq. NaHCO₃solution and brine. The organic layer was separated, dried overanhydrous Na₂SO₄ and concentrated at low pressure. The residue waspurified by silica gel column to give 25-2 (0.55, 85%) as a white solid.

To a solution of 25-2 (0.5 g, 0.5 mmol) in dry DMF (10 mL) was addedNaOBz (0.72 g, 5 mmol) and 15-crown-5 (0.9 mL). The mixture was stirredat 95° C. for 72 h. The mixture was diluted with EA, and washed withwater and brine. The organic phase was dried over MgSO₄ and concentratedat low pressure. The residue was purified by silica gel column (10% EAin PE) to give 25-3 (0.3 g, 60%) as a white solid.

Compound 25-3 (0.3 g, 0.3 mmol) in NH₃/MeOH (30 mL) was stirred at RTfor 18 h. The mixture was concentrated at low pressure, and the residuewas purified by silica gel column (20% EA in PE) to give 25-4 (145 mg,56%) as a white solid. ESI-LCMS: m/z 890.5 [M+H]⁺.

To a stirred solution of 25-4 (161 mg, 0.16 mmol) in anhydrous CH₃CN(2.0 mL) was added N-methylimidazole (118 μL, 2.87 mmol) at 0 to 5° C.(ice/water bath) followed by solution of 25-5 (186 mg, 0.54 mmol,dissolved in 2 mL of CH₃CN). The solution was stirred at 0 to 5° C. for4 h. The mixture was diluted with EA, and water was added (15 mL). Thesolution was washed H₂O, 50% aqueous citric acid solution and brine. Theorganic layer was separated, dried over anhydrous MgSO₄ and filtered.The filtrate was concentrated in vacuum to give a residue, which waspurified on silica gel with 0 to 40% EA/hexanes to give as 25-6 (82.6mg) as the faster eluting isomer and 25-7 (106 mg) as the slower elutingisomer.

Compound 25-6 (82.6 mg, 0.07 mmol) was dissolved in anhydrous CH₃CN (0.5mL), and 4N HCl in dioxane (35 μL) was added at 0 to 5° C. The mixturewas stirred at RT for 1 h, and anhydrous EtOH (100 μL) was added. Thesolvents were evaporated at RT and co-evaporated with toluene 3 times.The residue was dissolved in 50% CH₃CN/H₂O, and purified on areverse-phase HPLC (C18) using acetonitrile and water, followed bylyophilization to give compound 25 (19.4 mg). ¹H NMR (CD₃OD-d₄, 400 MHz)δ 7.9 (s, 1H), 7.32-7.28 (t, J=8.0 Hz, 2H), 7.2-7.12 (m, 3H), 6.43 (d,J=17.6 Hz, 1H), 4.70-4.63 (m, 2H), 4.55-4.4 (m, 3H), 3.94-3.9 (m, 1H),1.79-1.67 (m, 4H), 1.53-1.49 (m, 1H), 1.45-1.22 (m, 15H); ³¹P NMR(CD₃OD-d₄) δ 4.06 (s); ESI-LCMS: m/z=655.2 [M+H]⁺, 653.15 [M−H]⁻.

Compound 25-7 (100 mg, 0.083 mmol) was dissolved in anhydrous CH₃CN (0.5mL), and 4N HCl in dioxane (50 μL) was added at 0 to 5° C. Following theprocedure for obtaining compound 25, compound 26 (31.8 mg) was obtained.¹H NMR (CD₃OD-d₄, 400 MHz) δ 7.93 (s, 1H), 7.33-7.29 (m, 2H), 7.24-7.14(m, 3H), 6.41 (d, J=17.6 Hz, 1H), 4.70-4.60 (m, 2H), 4.54-4.49 (m, 2H),4.44-4.39 (m, 1H), 3.92-3.89 (m, 1H), 1.77-1.66 (m, 4H), 1.54-1.24 (m,16H); ³¹P NMR (CD₃OD-d₄) 33.91 (s); ESI-LCMS: m/z=655.2 [M+H]⁺, 653.1[M−H]⁻.

Example 22 Compounds 27 and 28

To a stirred suspension of 4-1 (50 g, 84.8 mmol) and2-amino-6-chloropurine (28.6 g, 169.2 mmol) in anhydrous MeCN (500 mL)was added DBU (77.8 g, 508 mmol) at 0° C. The mixture was stirred at 0°C. for 30 mins, and TMSOTf (150.5 g, 678 mmol) was added dropwise at 0°C. The mixture was stirred at RT for 20 mins until a clear solution wasformed. The mixture was stirred at 90-110° C. overnight. The mixture wascooled to RT, and diluted with EA. The solution was washed with sat.NaHCO₃ solution and brine. The organic layer was dried over Na₂SO₄ andthen concentrated at low pressure. The residue was purified by silicagel column (PE/EA=2/1) to give 27-1 (30 g, 55.5%) as a white solid.

To a solution of 27-1 (30 g, 47.1 mmol) in anhydrous DCM (300 mL) wasadded collidine (30 mL), AgNO₃ (24 g, 141.4 mmol) and MMTrCl (43.6 g,141.4 mmol). The mixture was stirred at RT overnight. The mixture wasfiltered, and the filtrate was washed with water and brine. The organiclayer was dried over anhydrous Na₂SO₄, and concentrated at low pressure.The residue was purified by silica gel column (PE/EA=4/1) to give 27-2(35 g, 82%) as a white solid.

To a stirred solution of 27-2 (35 g, 38.5 mmol) in anhydrous EtOH (150mL) was added a solution of EtONa in EtOH (2N, 150 mL). The mixture wasstirred at RT overnight, and then concentrated at low pressure. Theresidue was dissolved in EA (200 mL) and the solution was washed withwater and brine. The organic layer was dried over Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn (DCM/MeOH=100/2) to give 27-3 (19 g, 81%) as a white solid.

Compound 27-3 (19 g, 31.3 mmol) was co-concentrated with anhydrouspyridine for 3 times. To an ice cooled solution of 27-3 in anhydrouspyridine (120 mL) was added a solution of TsCl (6.6 g, 34.6 mmol) inpyridine (40 mL) dropwise at 0° C. The mixture was stirred at 0° C. for16 h. The mixture was quenched with water, and the reaction mixture wasconcentrated. The residue was re-dissolved in EA (200 mL). The solutionwas washed with sat. aq. NaHCO₃ and brine. The organic layer was driedover anhydrous Na₂SO₄ and filtered, and the filtrate was concentrated.The residue was purified by silica gel column (DCM/MeOH=100/1) to give27-4 (16 g, 67%) as a yellow solid.

To a solution of 27-4 (15 g, 19.7 mmol) in acetone (100 mL) was addedNaI (30 g, 197 mmol). The mixture was refluxed overnight, and thenconcentrated at low pressure. The residue was purified by silica gelcolumn (DCM/MeOH=100/1) to give 27-5 (9 g, 63.7%) as a white solid.

To a solution of 27-5 (8 g, 11.2 mmol) in anhydrous THF (60 mL) wasadded DBU (5.12 g, 33.5 mmol), and the mixture was heated at 60° C.overnight. The mixture was diluted with EA, and washed with water andbrine. The organic layer was dried over anhydrous Na₂SO₄ and filtered,and the filtrate was concentrated. The residue was purified by silicagel column (PE/acetone=4/1) to give 27-6 (5.7 g, 86%) as a white solid.¹H-NMR (CD₃OH, 400 MHz) δ=8.18 (s, 1H), 7.17-7.33 (m, 12H), 6.80 (d,J=8.8 Hz, 2H), 5.98 (s, 1H), 5.40 (d, J=8.6 Hz, 1H), 3.87 (m, 5H), 3.75(s, 3H), 2.69 (s, 1H), 1.05 (s, 3H).

To an ice cooled solution of 27-6 (4.44 g, 7.5 mmol) in anhydrous MeCN(45 mL) was added TEA.3HF (1.23 g, 7.6 mmol) and NIS (2.16 g, 9.5 mmol).The mixture was stirred at RT for 2-3 h. The reaction was quenched withsat. Na₂SO₃ and NaHCO₃ solution. The mixture was extracted with EA(3×100 mL). The organic layer was separated, dried over anhydrous Na₂SO₄and concentrated at low pressure. The residue was purified by silica gelcolumn (DCM/acetone=100/2) to give 27-7 (4.4 g, 79.8%) as a white solid.

To a solution of 27-7 (5.36 g, 7.3 mmol) in anhydrous DCM (50 mL) wasadded DMAP (3.6 g, 29.8 mmol) and BzCl (3.1 g, 22.1 mmol) at 0° C. Themixture was stirred at RT overnight. The mixture was washed with sat.aq. NaHCO₃ and brine. The organic layer was concentrated, and theresidue was purified by silica gel column (PE/EA=5/1) to give 27-8 (5.6g, 81.3%) as a white solid.

To a solution of 27-8 (5.0 g, 5.3 mmol) in anhydrous DMF (150 mL) wasadded NaOBz (7.64 g, 53 mmol) and 15-crown-5 (14 g, 68 mmol). Themixture was stirred at 90-100° C. for 48 h. The mixture was diluted withEA, and washed with water and brine. The organic layer was concentrated,and the residue was purified by silica gel column (PE/EA=5/1) to give27-9 (3.9 g, 78.5%) as a white solid.

Compound 27-9 in NH₃ in MeOH (7N, 60 mL) was stirred at RT for 18 h. Themixture was concentrated at low pressure. The residue was purified bysilica gel column (DCM/acetone=50/1) to give 27-10 (500 mg, 74.7%) as awhite solid. ESI-MS: m/z 626.3 [M+H]⁺.

To a solution of 27-10 (350 mg, 0.56 mmol) in anhydrous pyridine (4 mL)was added imidazole (50 mg, 0.72 mmol) and TBSCl (108 mg, 0.72 mmol) at0 to 5° C., and stirred at RT for 15 h. The reaction was quenched withabsolute EtOH (0.5 mL). The solution was concentrated to dryness underreduced pressure. The residue was dissolved in EA (150 mL), and washedwith water, sat. NaHCO₃ and brine. The combined organic layers weredried over Na₂SO₄, filtered and evaporated at low pressure. The residuewas purified by silica gel column (10-30% EA in hexanes) to give 27-11(338 mg, 81.8%) as a white solid.

To a solution of compound 27-11 (328 mg, 0.44 mmol), AgNO₃ (226 mg, 1.33mmol) and collidine (0.59 mL, 4.84 mmol) in anhydrous DCM (4 mL) wasadded MMTrCl (410 mg, 1.33 mmol) under N₂. The mixture was stirred at RTovernight under N₂, and monitored by TLC to completion. The mixture wasfiltered through pre-packed Celite filter, and the filtrate was washedwith water, 50% aqueous citric acid, and brine. The organic layer wasseparated, dried over anhydrous Na₂SO₄, filtered and concentrated at lowpressure. The residue was purified by silica gel column (EA in hexanesfrom 0% to 30%) to give 27-12 (337 mg).

To a solution of 27-12 (337 mg, 0.33 mmol) in anhydrous THF (4 mL) wasadded 1.0 M solution of TBAF (0.66 ML, 0.66 mmol) at 0 to 5° C. Thereaction was slowly warmed to RT, and stirred for 1 h. The mixture wasquenched with silica gel, and filtered. The solvents were evaporated togive the crude product, which was purified by silica gel column (EA inhexanes from 0% to 50%) to give 27-13 (188 mg).

To a stirred solution of 27-13 (180 mg, 0.16 mmol) in anhydrous CH₃CN(2.5 mL) was added N-methylimidazole (132 μL, 1.6 mmol) at 0-5° C.(ice/water bath) followed by solution ofphenyl(cyclohexanoxy-L-alaninyl)phosphorochloridate (207 mg, 0.6 mmol,dissolved in 2 mL of CH₃CN). The solution was stirred at RT for 2.5 h,and the mixture was diluted with EA followed by addition of water (15mL). The solution was washed H₂O, 50% aqueous citric acid solution andbrine. The organic layer was separated, dried over anhydrous MgSO₄ andfiltered. The filtrate was concentrated in vacuum to give a residue,which was purified on silica gel with 0 to 40% EA/hexanes to give 27-14(75.8 mg) and 27-15 (108 mg) as a slower eluting isomer.

Compound 27-14 (76 mg, 0.063 mmol) was dissolved in anhydrous CH₃CN (0.5mL), and 4N HCl in dioxane (47 μL) was added at 0 to 5° C. (ice/waterbath). The mixture was stirred at RT for 40 mins, and anhydrous EtOH(200 μL) was added. The solvents were evaporated at RT and co-evaporatedwith toluene 3 times. The residue was dissolved in 50% CH₃CN/H₂O,purified on a reverse-phase HPLC (C18) using acetonitrile and water, andlyophilized to give compound 27 (26.6 mg). ESI-LCMS: m/z=663.3 [M+H]⁺.

Compound 27-15 (108 mg, 0.089 mmol) was dissolved in anhydrous CH₃CN(0.7 mL), and 4N HCl in dioxane (67 μL) was added at 0 to 5° C.(ice/water bath). The mixture was stirred at RT for 60 mins, andanhydrous EtOH (200 μL) was added. The solvents were evaporated at RTand co-evaporated with toluene 3 times. The residue was dissolved in 50%CH₃CN/H₂O, purified on a reverse-phase HPLC (C18) using acetonitrile andwater, and lyophilized to give compound 28 (40.3 mg). ESI-LCMS:m/z=663.2 [M+H]⁺.

Example 23 Compounds 30 and 31

To a mixture of pre-silylated 6-Cl-guanine (using HMDS and (NH₄)₂SO₄)(25.2 g, 150 mmol) in DCE (300 mL) was added 30-1 (50 g, 100 mmol) andTMSOTf (33.3 g, 150 mmol) at 0° C. The mixture was stirred at 70° C. for16 h, and then concentrated at low pressure. The residue wasre-dissolved in EA, and washed with sat. aq. NaHCO₃ and brine. Theorganic layer was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified on silica gel column (PE/EA=2/1) togive pure 30-2 (45 g, 73%) as a white solid.

To a solution of 30-2 (45 g, 73.4 mmol) in EtOH (73 mL) was added withEtONa (1N in EtOH, 360 mL). The mixture was stirred at RT for 16 h. Themixture was then concentrated to give a residue, which was purified bysilica gel column (DCM/MeOH=10/1) to give pure 30-3 (19 g, 83%) as awhite solid.

To a solution of 30-3 (19 g, 61.1 mmol) in pyridine (120 mL) was addedwith TIPDSCl₂ (19.2 g, 61 mmol) dropwise at 0° C. The mixture wasstirred at RT for 16 h, and then concentrated at low pressure. Theresidue was re-dissolved in EA, and washed with sat. aq. NaHCO₃. Theorganic layer was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel column (DCM/MeOH=20/1)to give pure 30-4 (22 g, 65%) as a white solid.

To a solution of 30-4 (22 g, 39.8 mmol) in DMF/pyridine (5/1, 100 mL)was added TMSCl (12.9 g, 119 mmol) dropwise at 0° C. The mixture wasstirred at RT for 1 h and then treated with isobutyryl chloride (5.4 g,50 mmol). The mixture was stirred at RT for 3 h and then quenched byNH₄OH. The mixture was concentrated at low pressure. The residue wasdissolved in EA (200 mL). The solution was washed with sat. aq. NaHCO₃,and then the organic layer was dried and concentrated at low pressure.The residue was purified by silica gel column (DCM/MeOH=50/1) to givepure 30-5 (15 g, 60%) as a white solid.

To a solution of 30-5 (15 g, 24.1 mmol) in DCM (100 mL) was added PDC(13.5 g, 26 mmol) and Ac₂O (9.8 g, 96 mmol) at 0° C. The mixture wasstirred at RT for 16 h. The reaction was quenched by sat. aq. NaHCO₃,and then extracted with EA. The organic layer was dried over anhydrousNa2SO4, and concentrated at low pressure. The residue was dissolved inanhydrous THF (100 mL). To a solution of TMSCCH (12 g, 112 mmol) in THF(200 mL) was added n-BuLi (2.5 N, 44 mL) at −78° C. The mixture wasstirred at −78° C. for 15 mins and 0° C. for 15 mins. The mixture wastreated with a solution of crude ketone in THF at −78° C. and stirred at−30° C. for 2 h. The reaction was quenched by sat. aq. NH₄Cl, and thenextracted by EA. The combined organic layer was dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysilica gel column (PE/EA=10/1) to give pure 30-6 (3.1 g, 18%) as a whitesolid.

To a solution of 30-6 (7 g, 7.5 mmol) and pyridine (1.4 g, 17 mmol) inDCM (35 mL) was added with DAST (5.6 g, 35 mmol) at −78° C. The mixturewas stirred at −78° C. for 3 h. The reaction was quenched by sat. aq.NaHCO₃, and then extracted with EA. The combined organic layer was driedover anhydrous, and concentrated at low pressure. The residue waspurified by silica gel column (PE/EA=10/1) to give pure 30-7 (3.1 g,18%) as a white solid.

Compound 30-7 (4.1 g, 5.7 mmol) in sat. NH₃/MeOH (100 mL) was stirred atRT for 16 h, and concentrated at low pressure. The residue wasre-dissolved in anhydrous DCM (300 mL), and was treated with AgNO₃ (27.0g, 160 mmol), collidine (22 mL) and MMTrCl (23.0 g, 75.9 mmol) in smallportions under N₂. The mixture was stirred at RT for 16 h. The mixturewas filtered, and the filtrate was washed with sat. NaHCO₃ solution andbrine. The organic layer was separated, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn (PE/EA=10/1) to give the pure intermediate. The intermediate wasdissolved in a solution of TBAF/THF (1N, 20 mL). The mixture was stirredat RT for 2 h and then concentrated at low pressure. The residue waspurified by silica gel column (DCM/MeOH=50/1) to give pure 30-8 (3.0 g,86%) as a white solid.

To a solution of 30-8 (3.0 g, 4.9 mmol) in THF (50 mL) was addedimidazole (840 mg, 12 mmol), PPh₃ (3.2 g, 12 mmol), and I₂ (2.4 g, 9.2mmol) at 0° C. The mixture was stirred at RT for 16 h. The reaction wasquenched by sat. aq. Na₂S₂O₃, and then extracted with EA. The combinedorganic layer was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel column (PE/EA=2/1) togive crude 30-9 (4.2 g, >100%, containing TPPO) as a white solid.

To a solution of crude 30-9 in anhydrous THF (30 mL) was added DBU (2.7g, 18 mmol), and heated to 80° C. The mixture was stirred for 1 h andchecked by LCMS. The mixture was quenched by water, and extracted withEA. The organic layer was dried over anhydrous Na₂SO₄ and filtered, andthe filtrate was concentrated at low pressure. The residue was purifiedby silica gel column (PE/EA=2/1) to give 30-10 (2.0 g, 69%) as a whitesolid.

To an ice cooled solution of 30-10 (2.0 g, 3.38 mmol) in anhydrous MeCN(15 mL) was added NIS (777 mg, 3.5 mmol) and NEt₃.3HF (536 g, 3.3 mmol)at 0° C. The mixture was stirred at RT for 16 h and checked by LCMS.After completion, the mixture was quenched by sat. Na₂SO₃ and sat.NaHCO₃ solution, and extracted with EA. The organic layer was separated,dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified by silica gel column chromatography (PE/EA=10/1 to3/1) to give 30-11 (2.1 g, 84.0%) as a white solid.

To a solution of crude 30-11 (2.1 g, 2.85 mmol) in anhydrous DCM (100mL) was added DMAP (490 mg, 4 mmol), and BzCl (580 mg, 4 mmol) at 0° C.The mixture was stirred overnight and checked by LCMS. The reaction waswashed with sat. NaHCO₃ solution. The organic layer was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by silica gel column chromatography (PE/EA=8/1 to 3/1) to give30-12 (2.0 g, 83.4%) as a white solid.

To a solution of 30-12 (2.0 g, 2.4 mmol) in anhydrous DMF (60 mL) wasadded NaOBz (3.3 g, 23.0 mmol) and 15-crown-5 (5.11 g, 23 mmol). Themixture was stirred at 110° C. for 36 h. The reaction was quenched bywater, and the mixture was extracted with EA. The organic layer wasdried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified by silica gel column (PE/EA=5/1 to 3/1) to give30-13 (830 mg, 42.0%) as a white solid. ESI-MS: m/z 836.11 [M+H]⁺.

A solution of 30-13 (831 mg, 1.0 mmol) in anhydrous n-butylamine (4 mL)was stirred at RT for 3 h under N₂ atmosphere. The reaction wasmonitored by TLC. The solvent was evaporated in vacuo, and the residuewas purified by silica gel column (MeOH in DCM from 0% to 10%) to givethe crude product, which as re-purified using silica gel column to give30-14 as a light pink solid (563 mg).

To a solution of 30-14 (560 mg, 0.89 mmol) in anhydrous pyridine (5 mL)was added imidazole (78.6 mg, 1.16 mmol) and TBSCl (202 mg, 1.34 mmol)at 0 to 5° C. The mixture was stirred at RT for 15 h. The reaction wasquenched by adding absolute EtOH (0.3 mL). The solution was concentratedto dryness under reduced pressure, and co-evaporated with toluene 3times. The residue was dissolved in EA (150 mL), and washed with water,sat. NaHCO₃, and brine. The combined organic layer was dried overNa₂SO₄, filtered and evaporated at low pressure. The residue waspurified by silica gel column (0-20% EA in hexanes) to give 30-15 (303mg) as a white solid.

To a solution of 30-15 (303 mg, 0.41 mmol), AgNO₃ (208 mg, 1.23 mmol)and collidine (0.55 mL, 4.51 mmol) in anhydrous DCM (4 mL) was addedMMTrCl (378 mg, 1.3 mmol) under N₂. The mixture was stirred at RTovernight under N₂, and monitored by TLC. The mixture was filteredthrough pre-packed celite filter, and the filtrate was washed with waterand, 50% aqueous citric acid, and brine. The organic layer wasseparated, dried over anhydrous Na₂SO₄, filtered and concentrated at lowpressure. The residue was purified by silica gel column (EA in hexanesfrom 0% to 30%) to give 30-16 (374 mg, 90%).

To a solution of 30-16 (374 mg, 0.37 mmol) in anhydrous THF (4 mL) wasadded 1.0 M solution of TBAF (0.74 mL, 0.74 mmol) at 0 to 5° C. Themixture was stirred at RT for 1 h. The mixture was quenched with silicagel, and filtered. The solvents were evaporated to give the crudeproduct, which was purified by silica gel column (EA in hexanes from 0%to 50%) to give 30-17 (265 mg).

To a stirred solution of 30-17 (187.5 mg, 0.16 mmol) in anhydrous CH₃CN(2.5 mL) was added N-methylimidazole (136 μL, 1.66 mmol) at 0-5° C.(ice/water bath) followed by solution ofphenyl(cyclohexanoxy-L-alaninyl)phosphorochloridate (214 mg, 0.62 mmol,dissolved in 0.5 mL of CH₃CN). The solution was stirred at RT for 3 h,and then diluted with EA followed by the addition of water (15 mL). Thesolution was washed with H₂O, 50% aqueous citric acid solution andbrine. The organic layer was separated, dried over anhydrous MgSO₄ andfiltered. The filtrate was concentrated in vacuum to give a residue,which was purified on silica gel with 0 to 40% EA/hexanes to give(single isomers) of 30-18 (108 mg) Elution of the latter fraction gave(single isomers) of 30-19 (120 mg) as glassy solid.

Compound 30-18 (108 mg, 0.089 mmol) was dissolved in anhydrous CH₃CN(0.5 mL), and 4N HCl in dioxane (67 μL) was added at 0 to 5° C.(ice/water bath). The mixture was stirred at RT for 40 mins, andanhydrous EtOH (200 μL) was added. The solvents were evaporated at RTand co-evaporated with toluene 3 times. The residue was dissolved in 50%CH₃CN/H₂O, was purified on a reverse-phase HPLC (C18) using acetonitrileand water, followed by lyophilization to give compound 30 (26.6 mg) as awhite foam. ¹H NMR (CD₃OD-d₄, 400 MHz) δ 7.89 (s, 1H), 7.33-7.29 (m,2H), 7.20-7.13 (m, 3H), 7.17 (m, 1H), 6.62 (d, J=15.6 Hz, 1H), 5.39 (t,J=25.2 Hz, 1H), 4.75-4.42 (m, 6H), 3.92 (t, J=8.8 Hz, 1H), 3.24 (d,J=5.6 Hz, 1H), 1.76-1.51 (m, 5H), 1.45-1.25 (m, 12H); ³¹P NMR (CD₃OD-d₄)δ 4.04 (s); ESI-LCMS: m/z=665.2 [M+H]⁺.

Compound 31 (44.4 mg, single isomer) was obtained according to theprocedure described for compound 30 using 30-19. ¹H NMR (CD₃OD-d₄, 400MHz) δ 7.93 (s, 1H), 7.32 (t, J=8.0 Hz, 1H), 7.24 (d, J=7.6 Hz, 2H),7.16 (t, J=7.6 Hz, 1H), 6.61 (d, J=16.0 Hz, 1H), 4.68-4.60 (m, 2H),4.54-4.39 (m, 3H), 3.93-3.89 (m, 1H), 3.24 (d, J=5.6 Hz, 1H), 1.75-1.5(m, 5H), 1.48-1.23 (m, 12H); ¹⁹F NMR (CD₃OD-d₄) δ −122.95 (s),−155.84-155.99 (m); ³¹P NMR (CD₃OD-d₄) 33.94 (s); ESI-LCMS: m/z=665.15[M+H]⁺.

Example 24 Compound 32

To a solution of 3-hydroxypropanenitrile (27 g, 0.15 mol) in THF (150mL) was added NaH (8.4 g, 0.21 mol) at 0° C., and the mixture wasstirred for 1 h. at RT. Compound 10-3 (27 g, 0.03 mol) in THF (100 mL)was treated with this mixture at 0° C. The combined mixture was stirredfor 6 h. at RT. The reaction was quenched with H₂O, and extracted withEA. The organic layer was dried over anhydrous Na₂SO₄, and concentratedat low pressure. The residue was purified by column chromatography togive 32-1 (9.38 g, 55%).

To a solution of 32-1 (1 g, 1.76 mmol) and TsOH (1 g, 5.28 mmol) in DMF(4 mL) and acetone (8 mL) was added 2,2-dimethoxypropane (1.8 g, 17.6mmol) at RT. The mixture was heated to 50° C. for 3 h. The reaction wasquenched with H₂O (50 mL), and extracted with EA (3×50 mL). The organiclayer was dried over anhydrous Na₂SO₄, and concentrated at low pressure.The residue was purified by column chromatography to give 32-2 (520 mg,87%).

To a stirred solution of 32-2 (10.0 g, 29.6 mmol) in pyridine (100 mL)was added TBSCl (53.4 g, 35.6 mmol) at RT, and the mixture was stirredfor 5 h. The mixture was concentrated at low pressure, and the residuewas dissolved in EA (100 mL). The solution was washed with water andbrine. The organic layer was dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The crude product was co-evaporated withtoluene 3 times. To a solution of anhydrous crude product (2.0 g, 4.43mmol) in DCM (30 mL) was added DMTrCl (2.24 g, 6.65 mmol),2,4,6-trimethylpyridine (1.07 g, 8.86 mmol) and AgNO₃ (1.5 g, 8.86mmol). The mixture was stirred for 1.5 h. The mixture was filtered, andthe filtrate was washed with 0.5 N HCl solution. The solution was washedwith brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure to give the crude yellow solid. The crude yellow solid (7.2 g,10 mmol) was treated with a solution of NH₄F (7.2 g, 200 mmol) in MeOH(50 mL), and the mixture was heated to 50° C. for 8 h. The mixture wasconcentrated at low pressure. The residue was purified by silica gelcolumn to give 32-3 (4.8 g, 80%).

To a solution of 32-3 (200 mg, 0.33 mmol) in DCM (5 mL) was added TFA.Py(40 mg, 0.328 mmol), DMSO (0.15 mL), and DCC (191 mg, 0.99 mmol) at RT.The mixture was stirred for 6 h, and concentrated at low pressure. Theresidue was purified by silica gel column to give the product. To asolution of the product (0.2 g, 0.328 mmol) and HCHO (0.2 mL) in1,4-dioxane (2 mL) was added NaOH (0.4 mL, 2 M) at RT. The mixture wasstirred for 5 h. The mixture was then treated with NaBH₄ (24 mg, 0.66mmol), and stirred for 3 h. The mixture was diluted with EA (20 mL), andwashed with brine. The organic phase was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The residue was purified by silica gelcolumn to give 32-4 (125 mg, 60%).

To a solution of 32-4 (4 g, 6.25 mmol) in DCM (40 mL) was added pyridine(10 mL) and BzCl (920 mg, 15.6 mmol) at −78° C. The mixture was slowlywarmed up to RT. The reaction was monitored by LCMS. The mixture wasquenched with H₂O (40 mL), and extracted with DCM (3×50 mL). The organiclayer was washed brine, dried over anhydrous Na₂SO₄, and concentrated atlow pressure. The residue was purified by silica gel column to give 32-5(3.25 g, 70%).

To a solution of 32-5 (5.75 g, 7.7 mmol) in DCM (20 mL) was added DMTrCl(3.58 g, 11.1 mmol), 2,4,6-trimethyl-pyridine (1.87 g, 15.4 mmol) andAgNO₃ (2.63 g, 15.4 mmol), and stirred for 3 h. The mixture wasfiltered, and the filtrate was washed with 0.5 N HCl solution. Theorganic phase was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn to give 32-6 (6.25 g, 80%).

To a solution of 32-6 (4.3 g, 4.23 mmol) in MeOH (40 mL) was added NaOMe(0.82 g, 12.6 mmol) at RT, and stirred for 3 h. The mixture wasconcentrated at low pressure. The residue was dissolved in EA (30 mL),and washed with brine. The organic layer was dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysilica gel column to give 32-7 (2.89 g, 75%).

To a solution of 32-7 (0.5 g, 0.54 mmol) and pyridine (0.478 g, 5.4mmol) in DCM (4 mL) was slowly added a solution of Tf₂O (0.201 g, 0.713mmol) in DCM (3 mL) at −35° C. The mixture was warmed up to −5° C.slowly. The reaction was monitored by LCMS. The reaction was quenchedwith sat. NaHCO₃ solution, and extracted with DCM (3×20 mL). The organicphase was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn to give the product. To a solution of the product was added TBAFin THF (25 mL, 1N), and the mixture was stirred for 5 h at RT. Thereaction was monitored by LCMS. The mixture was concentrated at lowpressure, and the residue was purified by prep-HPLC to give 32-8 (221mg, 45%). ESI-MS: m/z 914.4 [M+H]⁺.

Compound 32-8 (2.14 g) was dissolved in 80% HCOOH (10 mL) and was at RTovernight. The solvent was evaporated to dryness, and the residuecrystallized from methanol twice. The crystals were dissolved in amixture of THF and 36% HCl 4:1 v/v and left overnight. The solvent wasevaporated, and the nucleoside was isolated by RP HPLC on Synergy 4micron Hydro-RP column (Phenominex). A linear gradient of methanol from0 to 60% with 0.1% HCOOH was used for elution. Compound 32 was obtained(370 mg, 48%). MS: m/z 316.2 [M−1].

Example 25 Compound 17

A solution of 17-1 (25 mg, 0.04 mmol) in 80% aq. HCOOH was kept at RTfor 3 h. The mixture was concentrated and coevaporated with toluene. Thecrude residue was purified on silica gel (10 g column) with CH₂Cl₂/MeOH(4-10% gradient) to yield 17-2 (8 mg, 54%).

A mixture of 17-2 (8 mg, 0.02 mmol) in acetonitrile (0.4 mL) was stirredwith NMI (15 mL, 8 eq.) and the phosphorochloridate reagent overnight atRT. The reaction was quenched with sat. aq. NH₄Cl, diluted with EtOAcand water. The organic layer was separated, washed with aq. NaHCO₃,water and brine, and dried (Na₂SO₄). The residue was purified on silicagel (10 g column) with CH₂Cl₂/i-PrOH (4-10% gradient) to yield compound17 (9 mg, 66%). MS: m/z=683 [M+1].

Example 26 Compound 35

To a stirred solution of 32-2 (5.0 g, 14.83 mmol) in anhydrous pyridine(50 mL) was added TBSCl (3.33 g, 22.24 mmol) at RT under N₂. The mixturewas stirred at RT for 12 h and concentrated at low pressure. The residuewas purified by silica gel column chromatography to give 35-1 (5.69 g,85.1%).

To a solution of PPh₃ (2.76 g, 10.6 mmol) and DIAD (2.15 g, 10.6 mmol)in dioxane (20 mL) was added EtOH (0.49 g, 10.6 mmol) at RT. Afterstirring for 30 mins, a solution of 35-1 (2.4 g, 5.3 mmol) in dioxane(10 mL) was added. The solution was stirred overnight at RT. After thereaction was complete, the reaction was quenched with sat. NaHCO₃solution. The solution was extracted with EA (3×40 mL). The organiclayer was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn (10% EA in PE) to give 35-2 (2 g, 78.4%) as a white solid.

To a solution of 35-2 (8 g, 16.9 mmol) in dichloromethane (60 mL) wasadded AgNO₃ (5.67 g, 33.4 mmol), collidine (4.03 g, 33.4 mmol) andMMTrCl (7.7 g, 25 mmol) in small portions under N₂ at 0° C. The mixturewas stirred at RT overnight. The reaction was monitored by TLC. Aftercompletion, the mixture was filtered. The filtrate was washed with sat.aq. NaHCO₃ and brine. The organic layer was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The residue was purified by silica gelcolumn to give 35-3 (10 g, 80%) as a white solid.

To a solution of 35-3 (10 g, 13.3 mmol) in methanol (100 mL) was addedNH₄F (10 g, 270 mmol), and heated to reflux overnight. The mixture wasconcentrated at low pressure. The residue was purified by silica gelchromatography (50% PE in EA) to give 35-4 as a white solid (5 g, 59%).

To a solution of 35-4 (4 g, 6.27 mmol) and DCC (3.65 g, 18.8 mmol) inanhydrous DMSO (40 mL) was added TFA.Py (1.21 g, 6.27 mmol) at RT underN₂. The mixture was stirred at RT overnight. The reaction was quenchedwith water (100 mL), and diluted with EA (200 mL). After filtration, thefilter was washed with sat. NaHCO₃ solution. The organic phase waswashed with brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue (4 g, 6.27 mmol) was dissolved in dioxane (40 mL),and 37% formaldehyde (4 mL) followed by addition of 2N NaOH solution (8mL) at RT. The mixture was stirred at 30° C. overnight. NaBH₄ (0.7 g,18.9 mmol) was added in portions at 5° C., and the mixture was stirredat RT for 30 mins. The reaction was quenched with water, and the mixturewas extracted with EA (3×50 mL). The organic layer was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified on a silica gel column (20% EA in PE) to give 35-5 (2.5 g, 60%)as a white solid.

To a solution of 35-5 (2.29 g, 3.43 mmol) in pyridine (5 mL) and DCM (20mL) was added BzCl (0.53 g, 3.77 mmol) at −78° C., and stirred overnightat RT. The mixture was quenched with water, and extracted with DCM (3×40mL). The organic layer was dried over anhydrous Na₂SO₄, and concentratedat low pressure. The residue was purified by silica gel column to givethe 35-6 (1.62 mg, 62%).

To a solution of 35-6 (1.62 g, 2.1 mmol) in dichloromethane (20 mL) wasadded AgNO₃ (714 mg, 4.2 mmol), collidine (508 mg, 4.2 mmol) and MMTrCl(970 mg, 3.2 mmol) in small portions under N₂ at 0° C. The mixture wasstirred at RT overnight. The reaction was monitored by TLC. Afterfiltration, the filter was washed with sat. aq. NaHCO₃ and brine. Thecombined organic layer was dried over anhydrous Na₂SO₄, and concentratedat low pressure. The residue was purified by silica gel column to give35-7 (2 g, 91.3%) as a white solid.

To a solution of 35-7 (2.1 g, 2 mmol) in MeOH (30 mL) was added NaOMe(220 mg, 4 mmol) at RT and stirred for 1 h. After all starting materialdisappeared as indicated by TLC, the reaction was quenched with dry ice,and evaporated at low pressure. The residue was purified by silica gelcolumn chromatography to give 35-8 (1.3 g, 69%) as a white solid.

To a solution of 35-8 (1.3 g, 1.38 mmol) in anhydrous DCM (15 mL) andpyridine (1 mL) was added dropwise Tf₂O (585 mg, 2.07 mmol) at −20° C.The mixture was stirred at RT for 3 h, and diluted with DCM (150 mL).The solution was washed successively with water and brine. The organicsolution was dried over Na₂SO₄ and concentrated at low pressure. Theresidue (1.48 g) was dissolved in anhydrous THF (15 mL), and treatedwith TBAF (3 mL, 1M in THF) at RT. The mixture was stirred overnight.The reaction was quenched with sat. aq. NaHCO₃, and extracted with EA(3×60 mL). The combined organic layer was dried over Na₂SO₄, andevaporated at low pressure. The residue was purified by silica gelcolumn (30% EA in PE) to give 35-9 (1.25 g, 96%) as a white solid.ESI-LCMS: m/z 942.4 [M+H]⁺.

Compound 35-9 (0.55 g, 0.58 mmol) was added into ice cooled 80% aq. TFA(5 mL) and kept overnight at 5° C. The mixture was concentrated underreduced pressure at 5° C. Thick oily residue was coevaporated severaltimes with toluene and purified on silica gel (10 g column) withCH₂Cl₂/MeOH (4-15% gradient) to yield compound 35 (75 mg, 36%). MS:m/z=358 [M+1].

Example 27 Compound 36

Compound 36 (8 mg, 10%) was prepared from compound 15 (48 mg) inacetonitrile (1.5 mL) with the phosphorochloridate reagent (0.14 g) andNMI (0.17 mL) in the same manner as compound 7. Purification was done byRP-HPLC (30-100% B, A: 50 mM TEAA in water, B: 50 mM TEAA in MeCN). MS:m/z=665 [M−1].

Example 28 Compound 38

To a solution of 38-1 (17 g, 65.9 mmol) and 2,2-dimethoxypropane (34.27g, 329.5 mmol, 5 eq.) in acetone (200 mL) was added p-toluenesulfonicacid monohydrate (11.89 g, 62.6 mmol, 0.95 eq.). The =mixture wasallowed to stir overnight at RT. The reaction was quenched with sat. aq.NaHCO₃. The mixture was filtered, and dried over anhydrous Na₂SO₄. Thefiltrate was concentrated to give 38-2 (19 g, 97%).

To a solution of 38-2 (6 g, 20.1 mmol) in anhydrous CH₃CN (80 mL) wasadded IBX (7.05 g, 25.2 mmol, 1.25 eq.) at RT. The mixture was refluxedfor 1 h., and cooled to 0° C. The precipitate was filtered, and thefiltrate was concentrated to give crude 38-3 (6 g 100%) as a yellowsolid.

Compound 38-3 (6 g 20.1 mmol) was dissolved in 1,4-dioxane (60 mL). 37%HCHO (6 mL, 69 mol) and 2M NaOH aqueous solution (12 mL, 24 mmol, 1.2eq.) were added at 10° C. The mixture was stirred at RT overnight andneutralized with AcOH to pH=7. The mixture was treated with NaBH₄ (1.53g, 40.2 mmol, 2 eq.) at 10° C. The mixture was stirred at RT for 30mins, and then quenched with sat. aq. NH₄Cl. The mixture was extractedwith EA. The organic layer was dried over anhydrous Na₂SO₄, andconcentrated to dryness. The residue was purified on silica gel column(1-3% MeOH in DCM) to give 38-4 (3.5 g, 53%) as a white solid.

To a solution of 38-4 (3.5 g, 10.7 mmol) in anhydrous pyridine (60 mL)was added DMTrCl (3.6 g, 10.7 mmol, 1 eq.) in anhydrous DCM (8 mL)dropwise at −30° C. The mixture was stirred at RT overnight. Thesolution was treated with MeOH, and concentrated to dryness at lowpressure. The residue was purified by column chromatography (0.5-2% MeOHin DCM) to give 38-5 (3 g, 45%) as a yellow solid.

To a solution of 38-5 (2.5 g, 4 mmol) in anhydrous CH₂Cl₂ (30 mL) wasadded AgNO₃ (0.816 g, 4.8 mmol, 1.2 eq.), imidazole (0.54 g, 8 mmol, 2eq.) and TBDPSCl (1.18 g, 4.8 mmol, 1.2 eq.) under N₂ atmosphere. Themixture was stirred at RT for 14 h. The precipitate removed viafiltration, and the filtrate was washed with brine and dried overNa₂SO₄. The solvent was removed under reduced pressure to give crude38-6 (3.4 g, 100%) as a yellow solid.

Compound 38-6 (4 g, 4.6 mmol) was dissolved in 80% HOAc aqueous solution(50 mL). The mixture was stirred at RT for 3 h. The solution was treatedwith MeOH, and concentrated to dryness. The residue was purified bycolumn chromatography (1-2% MeOH in DCM) to give 38-7 (1.2 g, 45%) as awhite solid.

To a solution of 38-7 (1 g, 1.77 mmol) in anhydrous DCM (15 mL) wasadded Dess-Martin periodinane reagent (1.12 g, 2.65 mmol, 1.5 eq.) at 0°C. under nitrogen atmosphere. The reaction was stirred at RT for 2.5 h.The solution was quenched by addition of 4% Na₂S₂O₃ and washed with 4%sodium bicarbonate aqueous solution (50 mL). The mixture was stirred foranother 15 mins. The organic layer was washed with brine, andconcentrated under reduced pressure. The residue was purified by silicagel column chromatography (20% EtOAc in hexane) to give 38-8 (0.7 g,70%) as a white solid.

To a solution of methyltriphenylphosphonium chloride (2.95 g, 8.51 mmol,4 eq.) in anhydrous THF (20 mL) was added n-BuLi (3.2 mL, 8.1 mmol, 3.8eq.) dropwise at −70° C. under nitrogen atmosphere. The mixture wasstirred at 0° C. for 1 h. A solution of 38-8 (1.2 g, 2.13 mmol) inanhydrous THF (3 mL) was added dropwise at 0° C. under nitrogenatmosphere. The solution was stirred 0° C. for 2 h. The reaction wasquenched with NH₄Cl and extracted with EtOAc. The organic layer waswashed with brine and concentrated under reduced pressure. The crudeproduct was purified by silica gel column chromatography (20% EtOAc inhexane) to give 38-9 (0.9 g, 75%) as a white solid.

To a solution of 38-9 (0.85 g, 1.43 mmol) in anhydrous THF (50 mL) wasadded n-BuLi (5.7 mL, 14.3 mmol, 10 eq.) at −70° C. under nitrogenatmosphere. The mixture was stirred at −70° C. for 2 h. The reaction wasquenched with NH₄Cl and extracted with EtOAc. The organic layer waswashed with brine and concentrated under reduced pressure. The crudeproduct was purified by silica gel column chromatography (20% EtOAc inhexane) to give 38-10 (0.4 g, 50%) as a white solid.

To a solution of 38-10 (0.4 g, 0.714 mmol) in anhydrous CH₃CN (30 mL)were added TPSCl (0.433 g, 1.43 mmol, 2 eq.), DMAP (0.174 g, 1.43 mmol,2 eq.) and TEA (1.5 mL) at RT. The mixture was stirred at RT for 3 h.NH₄OH (3 mL) was added, and the mixture was stirred for 1 h. The mixturewas diluted with EA (150 mL), and washed with water, 0.1 M HCl andsaturated aqueous NaHCO₃. The organic layer was washed with brine andconcentrated under reduced pressure. The crude product was purified bysilica gel column chromatography (2% MeOH in DCM) to give 38-11 (0.2 g,50%) as a yellow solid.

Compound 38-11 (1.35 g, 1.5 mmol) was dissolved in 80% HOAc aqueoussolution (40 mL). The mixture was stirred at 60° C. for 2 h andconcentrated to dryness. The crude was purified on silica gel column (5%MeOH in DCM) to give compound 38 (180 mg, 35%) as a white solid. ESI-MS:m/z 282.1 [M+H]⁺.

Example 29 Compound 39

To a solution of cyclopentanone (6.0 g, 71 mmol) in MeOH (60 mL) wasadded TsOH.H₂O (1.35 g, 7.1 mmol) and trimethoxymethane (8 mL) at RT.The solution was stirred at RT for 2 h. The reaction was quenched withNaOMe, and the mixture was extracted with hexane (30 mL). The organiclayer was dried and concentrated to give crude 1,1-dimethoxycyclopentane(9.2 g), which was dissolved in 1,2-dichloroethane (50 mL). To the abovesolution was added 38-1 (5.0 g, 19.38 mmol) and TsOH.H₂O (0.36 g, 1.9mmol) at RT. The mixture was stirred at 60° C. for 4 h. The reaction wasquenched with TEA and concentrated at low pressure. The residue waspurified on silica gel column (1% MeOH in DCM) to give 39-1 (4.77 g,76%) as a white solid.

To a solution of 39-1 (4.77 g, 14.73 mmol) in anhydrous DCM (50 mL) wasadded DMP (6.56 g, 15.6 mmol) at 0° C. The solution was stirred at RTfor 10 h and concentrated to dryness. The residue was suspended in PE(30 mL) and DCM (5 mL), and the solid was precipitated. Afterfiltration, the filtrate was concentrated to give the crude 39-2 (4.78g, 100%) as a foam.

Crude 39-2 (4.77 g, 14.73 mmol) was re-dissolved in anhydrous1,4-dioxane (50 mL). To the solution was added CH₂O aq. (37%, 3.6 mL)and NaOH aq. (2M, 11.3 mL) at 0° C. The mixture was stirred at RT for 16h. The mixture was treated with NaBH₄ (1.48 g, 40 mmol) at 0° C. andstirred for 0.5 h. The reaction was quenched with water, and the mixturewas extracted with EA. The organic layer was dried over anhydrousNa₂SO₄, and concentrated to dryness. The residue was purified on silicagel column (40% EA in PE) to give 39-3 (2.6 g, 49.9%) as a white solid.

To a stirred solution of 39-3 (5.0 g, 14.1 mmol) in pyridine (5.6 g, 71mmol) and DCM (100 mL) was added Tf₂O (8.7 g, 31.2 mmol) dropwise at−35° C. The mixture was allowed to warm to 0° C. slowly and stirred for2 h. The mixture was quenched with 0.5M aq. HCl and the DCM layer wasseparated. The organic phase was dried over anhydrous Na₂SO₄, andconcentrated to dryness. The crude was purified on silica gel column(20% EA in PE) to give 39-4 (4.5 g, 52%).

39-4 (4.5 g, 7.28 mmol) was dissolved in anhydrous THF (50 mL) at 0° C.The solution was treated with NaH (60% in mineral oil, 0.32 g, 8 mmol,1.1 eq.) in portions, and the mixture was stirred at R.T. for 8 h. Thereaction was quenched with water, and extracted with EA (3×60 mL). Theorganic layer was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure to give the crude product used directly fornext step. To a solution of the crude product (2.0 g, 3.6 mmol) in MeCN(10 mL) was added LiCl (4.0 g, 13 mmol). The reaction was allowed toproceed overnight. Aqueous NaOH (1N, ˜2 eq.) was added, and the mixturewas stirred for 1 h. The mixture was partitioned between sat. NH₄Clsolution and EA. The organic layer was concentrated under reducedpressure, and the crude was purified on silica gel column (20% EA in PE)to give 39-6 (0.6 g, 46%) as a white solid. ESI-MS: m/z 395.0 [M+Na]⁺.

Compound 39-6 (3.0 g, 8.06 mmol) was co-evaporated with toluene (30 mL).To a solution of 39-6 (3.0 g, 8.06 mmol), DMAP (98 mg, 0.80 mmol) andTEA (2.3 mL, 2 eq.) in DCM (30 mL) was added Bz₂O (1.82 g, 8.06 mmol) at0° C. and stirred for 3 h. The reaction was quenched with 1.0 M HCl andextracted with DCM. The DCM layer was dried over high vacuum pump togive crude 39-7 (3.3 g, 80.9%).

To a solution of 39-7 (400 mg, 0.84 mmol) in anhydrous CH₃CN (3 mL) wasadded TPSCl (507 mg, 1.68 mmol), TEA (169 mg, 1.68 mmol) and DMAP (207mg, 1.68 mmol), and the mixture was stirred for 2 h. at RT. Completionof the reaction was determined by TLC. Ammonium solution (3.0 mL) wasadded at RT, and the solution was stirred for 2 h. The mixture waswashed with 1.0 M HCl solution and extracted with DCM. The DCM layer wasdried over Na₂SO₄ and concentrated to dryness. The crude was purified bycolumn chromatography to provide 39-8 (250 mg, 63%).

Compound 39-8 (250 mg, 0.53 mmol) in 80% formic acid (3 mL) was stirredat RT for 3 h. Completion of the reaction was determined by TLC. Themixture was concentrated at a low pressure. The crude was purified bycolumn chromatography to give 39-9 (130 mg, 66%).

Compound 39-9 (270 mg, 0.73 mmol) was dissolved in MeOH/NH₃ (10 mL), andthe solution was stirred for 6 h. The mixture was concentrated at lowpressure. The crude product was washed with DCM, and the solution waslyophilized to give compound 39 (118 mg, 52%). ESI-MS: m/z 328.3[M+H+Na]⁺.

Example 30 Compound 40

Compound 40-1 (3.0 g, 8.42 mmol) was co-evaporated with toluene (30 mL).To a solution of 40-1 (3.0 g, 8.42 mmol), DMAP (103 mg, 0.84 mmol) andTEA (2.5 mL, 2 eq.) in DCM (30 mL) was added Bz₂O (2.01 g, 8.42 mmol) at0° C. and stirred for 3 h. The solution was quenched with 1.0 M HCl andextracted with DCM. The DCM layer was dried over high vacuum pump togive crude 40-2 (3.3 g, 85%).

To a solution of 40-2 (200 mg, 0.43 mmol) in anhydrous CH₃CN (2 mL) wasadded TPSCl (260 mg, 0.86 mmol), TEA (95 mg, 0.94 mmol) and DMAP (106.4mg, 0.86 mmol), and the mixture was stirred for 2 h at RT. Completion ofthe reaction was determined by TLC. Ammonium solution (1.33 mL) wasadded at RT, and left to stir for 2 h. The mixture was washed with 1.0 MHCl solution, and extracted with DCM. The DCM layer was dried overanhydrous Na₂SO₄, and concentrated to dryness at low pressure. Theresidue was purified by column chromatography to provide 40-3 (150 mg,75%).

Compound 40-3 (100 mg, 0.21 mmol) in 80% formic acid (2 mL) was stirredat RT for 3 h. Completion of the reaction was determined by TLC. Themixture was concentrated at low pressure, and the residue was purifiedby column chromatography to give 40-4 (50 mg, 58%).

Compound 40-4 (270 mg, 0.68 mmol) was dissolved in MeOH/NH₃ (10 mL), andthe resulting solution was stirred for 6 h. The mixture was concentratedat low pressure. The crude product was washed with DCM, and the solutionwas lyophilized to give compound 40 (105 mg, 53.8%). ESI-MS: m/z 290.4[M+H]⁺.

Example 31 Compound 41

Compound 41-1 (3.0 g, 8.87 mmol) was co-evaporated with toluene (30 mL).To a solution of 41-1 (3.0 g, 8.87 mmol), DMAP (108 mg, 0.88 mmol) andTEA (2.5 mL, 2 eq.) in DCM (30 mL) was added Bz₂O (2.01 g, 8.87 mmol) at0° C. The solution was stirred for 3 h. The reaction was quenched with1.0 M HCl solution, and extracted with DCM. The DCM layer was dried overhigh vacuum pump to give crude 41-2 (3.5 g, 85%) as a solid.

To a solution of 41-2 (200 mg, 0.45 mmol) in anhydrous CH₃CN (2 mL) wasadded TPSCl (260 mg, 0.90 mmol), TEA (99 mg, 0.99 mmol) and DMAP (106.4mg, 0.90 mmol). The mixture was stirred at RT for 2 h. Completion of thereaction was determined by TLC. An ammonium solution (1.33 mL) was addedat RT, and the mixture was stirred for 2 h. The mixture was washed with1.0 M HCl solution, and extracted with DCM. The DCM layer was dried overanhydrous Na₂SO₄, and concentrated to dryness at low pressure. The crudeproduct was purified by column chromatography to provide 41-3 (150 mg,75%).

Compound 41-3 (100 mg, 0.23 mmol) in 80% formic acid (2 mL) was stirredat RT for 3 h. Completion of the reaction was determined by TLC. Themixture was concentrated at a low pressure. The crude product waspurified by column chromatography to give 41-4 (50 mg, 58%).

Compound 41-4 (270 mg, 0.72 mmol) was dissolved in MeOH/NH₃ (10 mL), andthe solution was stirred for 6 h. The mixture was concentrated at lowpressure. The crude product was washed with DCM, and the solution waslyophilized to give compound 41 (105 mg, 53.8%). ESI-MS: m/z 675.4[2M+H]+.

Example 32

To a solution of 42-1 (600 mg, 1.29 mmol) in anhydrous CH₃CN (4 mL) wasadded DMAP (315 mg, 2.59 mmol), TEA (391 mg, 3.87 mmol) and TPSCl (782mg, 2.58 mmol). The mixture was stirred for 3 h. under N₂. A solution ofNH₃ in THF (2 mL) was added, and stirred for 1 h. The reaction wasquenched with sat. NH₄Cl solution, and extracted with EA. The organiclayer was dried over anhydrous Na₂SO₄, and concentrated to dryness atlow pressure. The residue was purified by column chromatography toprovide 42-2 (370 mg, 62%) as a white foam solid.

Compound 42-2 (370 mg, 1.48 mmol) in methanolic ammonium was stirred atRT for 4 h. The solution was concentrated to dryness to give compound 42(200 mg, 91%) as a white solid. ESI-MS: m/z 275.9 [M+H]⁺.

Example 33 Compound 43

To a solution of triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.6 mmol, prepared frombis(POC)phosphate (0.2 g) and Et₃N (83 μL)) in THF was added 43-1 (74mg, 0.2 mmol). The mixture evaporated and rendered anhydrous byco-evaporating with pyridine follow by toluene. The residue wasdissolved in anhydrous THF (2 mL). Diisopropylethylamine (0.35 mL; 10eq.) was added, followed by BOP-Cl (0.25 g; 5 eq.) and3-nitro-1,2,4-triazole (0.11 g; 5 eq.). The mixture was stirred at RTfor 90 mins, diluted with EtOAc, washed with sat. aq. NaHCO₃ and brine,and dried with Na₂SO₄. The residue was purified on silica (10 g column)with CH₂Cl₂/i-PrOH (4-10% gradient) to yield 50 mg (37%) of give 43-2.

A solution of 43-2 (40 mg; 0.06 mmol) in 80% aq. HCOOH was heated at 45°C. for 8 h. The mixture was evaporated, co-evaporated with toluene andpurified on silica (10 g column) with CH₂Cl₂/MeOH (4-10% gradient) toyield compound 43 (35 mg, 91%). MS: m/z=619 [M+1].

Example 34 Compound 44

Compound 44-2 was prepared from 40-1 following a similar procedure forthe preparation of 43-2. The residue was purified on silica (10 gcolumn) with hexanes/EtOAc (35-100% gradient) to yield 44-2 (0.45 g,75%).

A solution of 44-2 (0.40 g; 0.6 mmol) in 80% aq. HCOOH (15 mL) washeated at 45° C. for 8 h. The mixture was evaporated, co-evaporated withtoluene and purified on silica (10 g column) with CH₂Cl₂/MeOH (4-10%gradient) to yield compound 44 (0.27 g, 75%). MS: m/z=603 [M+1].

Example 35 Compound 45

To a solution of 45-1 (3.0 g, 4.7 mmol) in CH₃CN/pyridine (15 mL/20 mL)was added BzCl (0.67 g, 4.7 mmol) at 0° C. slowly. The mixture wasstirred at 10° C. for 12 h. The reaction was quenched with sat. NaHCO₃solution, and extracted with DCM. The solution was washed with brine,dried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified on silica gel column (EA in PE from 2% to 50%) toafford 45-2 (2.6 g, 72%) as a solid.

To a solution of 45-2 (1.0 g, 1.35 mmol) in pyridine (8 mL) was addedDMTrCl (0.64 g, 1.9 mmol). The mixture was stirred at 20-35° C.overnight. The reaction was monitored by LCMS and TLC. The reaction wasquenched with MeOH, and concentrated at low pressure. The residue waspurified by silica gel column to give 45-3 (1.5 g), which was usedwithout further purification.

To a solution of 45-3 (1.5 g, 1.35 mmol) in MeOH/THF (1/1, 10 mL) wasadded NaOMe (0.11 g, 2.0 mmol), and stirred at 40° C. for 3 h. Thereaction was monitored by TLC. The reaction was quenched with dry ice,and concentrated to dryness at low pressure. The residue was dissolvedin DCM (100 mL). The solution was washed with brine, dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified on silica gel column (EA in PE from 2% to 50%) to provide 45-4(1.0 g, 79%).

To a solution of 45-4 (950 mg, 1.02 mmol) in DCM (5 mL) was addedpyridine (241 mg, 3.05 mmol) and Tf₂O (344 mg, 1.22 mmol) at 0° C.slowly. The mixture was stirred at RT for 12 h. Completion of thereaction was determined by TLC and LCMS. The reaction was quenched withsat. NaHCO₃ solution, and extracted with DCM (3×60 mL). The organicphase was dried over anhydrous Na₂SO₄, and concentrated at low pressureto give crude 45-5 (1.08 g, 1.02 mmol), which was used without furtherpurification.

To a solution of 45-5 (1.08 g, 1.02 mmol) in THF (6 mL) was added TBAF(0.8 g, 3 mmol), and stirred at 30-40° C. for 12 h. The reaction wasquenched with sat. NaHCO₃ solution, and extracted with EA (3×60 mL). Thesolution was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel column (EA in PE from2% to 50%) to afford 45-6 (0.62 g, 65%).

A mixture of 45-6 (0.55 g, 0.59 mmol) in TFA (90%, 5 mL) was stirred at50-60° C. for 16 h. The mixture was treated with MeOH, and concentratedat low pressure. The residue was purified by prep-HPLC to affordcompound 45 (60 mg, 31%). ESI-MS: m/z 324.0 [M+H]⁺.

Example 36 Compound 46

To a solution of triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.33 mmol, prepared from110 mg of bis(POC)phosphate and 46 μL of Et₃N) in THF was added 46-1 (91mg, 0.11 mmol). The mixture evaporated and rendered anhydrous byco-evaporating with pyridine follow by toluene. The residue wasdissolved in anhydrous THF (1.5 mL) and cooled in an ice-bath.Diisopropylethylamine (0.19 mL, 10 eq.) was added, followed by BOP-Cl(0.14 g, 5 eq.), and 3-nitro-1,2,4-triazole (63 mg, 5 eq.). The mixturewas stirred 0° C. for 90 mins, diluted with EtOAc (30 mL), washed withsat. aq. NaHCO₃, brine, and dried (Na₂SO₄). The residue was purified onsilica (10 g column) with CH₂Cl₂/i-PrOH solvent system (2-10% gradient)to obtain 46-2 (13 mg, 10%) and 46-3 (95 mg, 58%).

A solution of 46-2 and 46-3 (13 mg and 95 mg, respectively) in 80% aq.HCOOH (3 mL) was stirred at RT for 3 h, then evaporated andco-evaporated with toluene. The residue was purified on silica (10 gcolumn) with CH₂Cl₂/MeOH (4-10% gradient) to obtain compound 46 in (42mg, 94%) yield. MS: m/z=628 [M+1].

Example 37 Compound 47

Compound 47-1 (320 mg, 0.51 mmol) was dissolved in a mixture ofCH₃COOH/THF/H₂O (4/2/1) (7 mL), and the mixture was stirred at 50° C.for 2 h. The solution was concentrated to dryness, and the residue waspurified by prep-HPLC to give compound 47 (38 mg, 31%) as a white solid.ESI-MS: m/z 296.9 [M+H+Na]⁺.

Example 38 Compound 48

To a stirred solution of 48-1 (30.0 g, 116 mmol) in anhydrous pyridine(240 mL) was added TIPDSCl (54.98 g, 174 mmol) in portions at 0° C. Themixture was stirred at RT for 16 h. The reaction was quenched withwater, and concentrated to dryness at low pressure. The residue wasdiluted with EA, and washed with water and brine. The organic phase wasdried over sodium sulfate, and concentrated at low pressure. The residuewas purified on a silica gel column (50% EA in PE) to give 48-2 (58 g,99%).

To a stirred solution of 48-2 (20.0 g, 40 mmol) in anhydrous DCM (200mL) at 0° C. was added DHP (33.6 g, 400 mmol) and TFA (6.84 g, 60 mmol)dropwise. The mixture was stirred at RT for 16 h. The solution wasadjusted to pH=8 by addition of 2 N NaOH solution. The mixture waswashed with sat. aq. NaHCO₃, and extracted with DCM (100 mL). Theorganic phase was dried over anhydrous sodium sulfate, and concentratedto dryness at low pressure. The residue was purified on a silica gelcolumn (20% EA in PE) to give 48-3 (16 g, 68%).

To a solution of 48-3 (41 g, 70 mmol) in anhydrous MeOH (400 mL) wasadded NH₄F (51.88 g, 140 mmol). The mixture was refluxed for 1 h, andthen concentrated in vacuum. The residue was purified on a silica gelcolumn (10% MeOH in DCM) to give 48-4 (23.1 g, 96%)

To a stirred solution of 48-4 (23.1 g, 67.54 mmol) in anhydrous pyridine(200 mL) was added imidazole (6.89 g, 101.32 mmol) and TBSCl (10.92 g,74.29 mmol) in portions at 0° C. The mixture was stirred at RT for 16 h.The solution was quenched with water, and concentrated to dryness. Theresidue was diluted with EA, and washed with water and brine. Theorganic phase was dried over anhydrous sodium sulfate, and concentratedat low pressure. The residue was purified on a silica gel column to give48-5 (23 g, 74%).

To a solution of 48-5 (27.56 g, 60.44 mmol) in anhydrous MeCN (560 mL)was added DMAP (18.43 g, 151.1 mol) and PhOCSCl (14.55 g, 84.61 mmol) at0° C. under N₂. The mixture was stirred at RT overnight, and thereaction was quenched with water. The mixture was extracted with EA. Theorganic phase was dried with anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified on a silica gel column eluted with30% EA in PE to provide 48-6 (23 g, 64%).

To a solution of 48-6 (14.5 g, 24.5 mmol) in anhydrous toluene (700 mL)was added AIBN (1.21 g, 7.3 mmol) and Bu₃SnH (10.73 g, 36.74 mmol) intoluene (10 mL). N₂ was bubbled into the solution for 30 mins. Themixture was warmed to 135° C. for 2 h. Saturated aqueous CsF was added,and the mixture was stirred for 1 h. The mixture was diluted with EA(150 mL), and washed successively with water, sat. aq. NaHCO₃ and brine.The organic layer was removed at low pressure. The residue was purifiedon a silica gel column (30% EA in PE) to provide 48-7 (10.5 g, 97%).

To a solution of 48-7 (21 g, 47.73 mmol) in anhydrous MeOH (200 mL) wasadded NH₄F (35.32 g, 950 mmol). The mixture was refluxed for 1 h andconcentrated in vacuum. The residue was purified on a silica gel column(20% MeOH in DCM) to give 48-8 (14 g, 90%).

TFA.Py (2.37 g, 12.27 mmol) was added to a mixture of 48-8 (4 g, 12.27mmol) and DCC (7.58 g, 36.81 mmol) in anhydrous DMSO (40 mL) at RT underN₂ atmosphere. The mixture was stirred at RT for 2 h. 37% formaldehyde(10 mL, 115 mmol) was added at RT, and stirred for 15 mins, followed bytreatment with 2N NaOH (20 mL, 40 mmol). The mixture was stirred at 30°C. overnight and neutralized with AcOH to pH=7. NaBH₄ (1.87 g, 49.08mmol) was added in portions at 5° C., and the mixture was stirred at RTfor 30 mins. The mixture was extracted with EtOAc (3×100 mL). Theorganic layer was dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified on a silica gel column (5% MeOH inDCM) to give 48-9 (2 g, 46%) as a white solid.

To a solution of 48-9 (2 g, 5.62 mmol) in anhydrous CH₃CN (8 mL) wasadded pyridine (10 mL) and BzCl (0.79 g, 5.62 mmol) in a solution of DCM(2 mL) at 0° C. under N₂. The mixture was stirred at RT overnight. Thereaction was quenched with water, and concentrated at low pressure. Theresidue was diluted with EA (50 mL), and washed successively with waterand brine. The organic layer was dried over anhydrous Na₂SO₄, andconcentrated at a low pressure. The residue was purified on a silica gelcolumn (3% MeOH in DCM) to provide 48-10 (1.6 g, 62%)

To a solution of 48-10 (1.6 g, 3.48 mmol) in anhydrous pyridine (16 mL)was added MMTrCl (1.61 g, 5.22 mmol) at 0° C. under N₂. The mixture wasstirred at RT overnight. The reaction was quenched with water, andconcentrated in vacuo. The residue was diluted with EA (50 mL) andwashed successively with water and brine. The organic layer was driedover Na₂SO₄ and concentrated at a low pressure to give crude 48-11 (2.55g, 100%), which used without further purification.

To a solution of 48-11 (2.55 g, 3.48 mmol) in anhydrous MeOH (50 mL) wasadded NaOCH₃ (0.28 g, 5.23 mmol). The mixture was stirred at 45° C. for2 h, bubbled to pH=7 by using dry ice and concentrated to dryness. Theresidue was purified on a silica gel column (2% MeOH in DCM) to give48-12 (0.93 g, 42%).

To a solution of 48-12 (0.93 g, 1.48 mmol) in anhydrous DCM (10 mL) wasadded pyridine (1.17 g, 14.8 mmol) at −30° C. Tf₂O (0.63 g, 2.22 mmol)in DCM (3 mL) was added dropwise. The mixture was stirred at −30° C.-0°C. for 20 mins and at 0° C. for 10 mins. The reaction was quenched withwater, and the mixture was extracted with DCM (3×100 mL). The organiclayer was dried over anhydrous Na₂SO₄, and concentrated at low pressureto provide crude 48-13 (1.13 g, 100%), which was used without furtherpurification.

To a solution of 48-13 (1.13 g, 1.48 mmol) in anhydrous THF (10 mL) wasadded TBAF (3.86 g, 14.8 mmol). The mixture was stirred at 30° C. for 2h. The reaction was quenched with water, and the mixture was extractedwith EtOAc (3×100 mL). The organic layer was dried over anhydrousNa₂SO₄, and concentrated to dryness at low pressure. The residue waspurified on a silica gel column (3% MeOH in DCM) to give 47-1 (0.42 g,45%).

To a solution of 47-1 (50 mg, 0.079 mmol) in anhydrous CH₃CN (1 mL) wasadded TPSCl (48.07 mg, 0.16 mmol), DMAP (19.36 mg, 0.16 mmol) and NEt₃(0.2 mL) at RT. The mixture was stirred at RT for 3 h. 28% aqueousammonia (0.4 mL) was added, and the mixture was stirred for 1 h. Themixture was diluted with EA (150 mL), and washed successively withwater, sat. aq. NaHCO₃ and brine. The organic layer was dried overanhydrous Na₂SO₄, and concentrated at a low pressure. The residue waspurified on a silica gel column (5% MeOH in DCM) to give 48-14 (40 mg,80%).

Compound 48-14 (320 mg, 0.51 mmol) was dissolved in 80% HCOOH (6 mL),and the mixture was stirred at 10° C. for 1 h. The mixture wasconcentrated at low pressure, and the residue was purified by prep-HPLCto give compound 48 (43 mg, 31%) as a white solid. ESI-MS: m/z 273.9[M+H]⁺, 547.1 [2M+H]⁺.

Example 39 Compound 49

To a solution of 49-1 (20.0 g, 70.2 mmol) in anhydrous pyridine (200 mL)was added imidazole (19.1 g, 280 mmol) and TBSCl (42.1 g, 281 mmol) at25° C. The solution was stirred at 25° C. for 15 h, and thenconcentrated to dryness under reduced pressure. The residue wasdissolved in EtOAc and then filtered. The filtrate was concentrated todryness to give the TBS protected derivative (36.4 g, 99%). The TBSprotected derivative (36.5 g, 71.1 mmol) was dissolved in THF (150 mL).H₂O (100 mL), and then AcOH (300 mL) were added. The solution wasstirred at 80° C. for 13 h. The reaction was cooled to RT, and thenconcentrated to dryness under reduced pressure to give 49-2 (31.2 g,61%) as a white solid.

To a solution of 49-2 (31.2 g, 78.2 mmol) in anhydrous pyridine (300 mL)was added Ac₂O (11.9 g, 117.3 mmol). The mixture was stirred at 25° C.for 18 h. MMTrCl (72.3 g, 234.6 mmol) and AgNO₃ (39.9 g, 234.6 mmol)were added, and the solution was stirred at 25° C. for 15 h. H₂O wasadded to quench the reaction and the solution was concentrated todryness under reduced pressure. The residue was dissolved in EtOAc andwashed with water. The organic layer was dried over Na₂SO₄ and filtered.The filtrate was concentrated in vacuum to give a residue, which waspurified by silica gel (DCM:MeOH=200:1 to 50:1) to give the MMTrprotected amine derivative (35.2 g, 63%). The MMTr protected aminederivative (35.2 g, 49.3 mmol) was dissolved in NH₃/MeOH (300 mL). Themixture was stirred at 25° C. for 20 h. The solution was evaporated todryness, and purified by a silica gel column (DCM: MeOH=100:1 to 50:1)to give 49-3 as a yellow solid (28.6 g, 87%).

To a solution of 49-3 (12.0 g, 17.9 mmol) in anhydrous DCM (200 mL) wasadded Dess-Martin periodinane (11.3 g, 26.8 mmol) at 0° C. The mixturewas stirred at 0° C. for 2 h, and then at RT for 2 h. The mixture wasquenched with a saturated NaHCO₃ and Na₂S₂O₃ solution. The organic layerwas washed with brine (2×) and dried over anhydrous Na₂SO₄. The solventwas evaporated to give the aldehyde (12.6 g), which was used directly inthe next step. To a solution of the aldehyde (12.6 g, 18.0 mmol) in1,4-dioxane (120 mL) was added 37% HCHO (11.6 g, 144 mmol) and 2N NaOHaqueous solution (13.5 mL, 27 mmol). The mixture was stirred at 25° C.overnight. EtOH (60 mL) and NaBH₄ (10.9 g, 288 mmol) were added, and thereaction was stirred for 30 mins. The mixture was quenched withsaturated aqueous NH₄Cl, and then extracted with EA. The organic layerwas dried over Na₂SO₄, and purified by silica gel column chromatography(DCM: MeOH=200:1 to 50:1) to give 49-4 (7.5 g, 59%) as a yellow solid.

To a solution of 49-4 (3.8 g, 5.4 mmol) in DCM (40 mL) was addedpyridine (10 mL) and DMTrCl (1.8 g, 5.4 mmol) at 0° C. The solution wasstirred at 25° C. for 1 h. MeOH (15 mL) was added, and the solution wasconcentrated. The residue was purified by silica gel columnchromatography (DCM: MeOH=200:1 to 50:1) to give the MMTr protectedderivative (3.6 g, 66%) as a yellow solid. To a solution of the MMTrprotected derivative (3.6 g, 3.6 mmol) in anhydrous pyridine (30 mL) wasadded TBDPSCl (2.96 g, 10.8 mmol) and AgNO₃ (1.84 g, 10.8 mmol). Themixture was stirred at 25° C. for 15 h. The mixture was filtered andconcentrated. The mixture was dissolved in EtOAc and washed with brine.The organic layer was dried over Na₂SO₄, and then purified by silica gelcolumn chromatography (DCM: MeOH=200:1 to 50:1) to give the TBDPSprotected derivative (3.8 g, 85.1%) as a solid. To a solution of theTBDPS protected derivative (3.6 g, 2.9 mmol) in anhydrous DCM (50 mL)was added Cl₂CHCOOH (1.8 mL) in anhydrous DCM (18 mL). The mixture wasstirred at −78° C. for 1 h. Cl₂CHCOOH (3.6 mL) was added at −78° C. Themixture was stirred at −10° C. for 30 mins. The mixture was quenchedwith saturated aqueous NaHCO₃ and extracted with DCM. The organic layerwas dried over Na₂SO₄, and then purified by silica gel columnchromatography (DCM: MeOH=200:1 to 50:1) to give 49-5 (2.2 g, 80%).

To an ice cooled solution of 49-5 (800 mg, 0.85 mmol) in anhydrous DCM(20 mL) was added pyridine (336 mg, 4.25 mmol) and Tf₂O (360 mg, 1.28mmol) dropwise. The reaction mixture was stirred at 0° C. for 15 mins.The reaction was quenched by ice water and stirred for 30 mins. Themixture was extracted with EtOAc, washed with brine (50 mL) and driedover MgSO₄. The solvent was evaporated to give the crude bis(triflate)derivative. To the bis(triflate) derivative (790 mg, 0.73 mmol) inanhydrous DMF (35 mL) was added LiCl (302 mg, 7.19 mmol). The mixturewas heated to 40° C. and stirred overnight. Completion of the reactionwas determined by LCMS. The solution was washed with brine and extractedwith EtOAc. The combined organic layers were dried over MgSO₄, and theresidue was purified on a silica gel column (DCM/MeOH=100:1) to give49-6 (430 mg, 61%).

To 49-6 (470 mg, 0.49 mmol) in MeOH (85 mL) was added NH₄F (8.1 g, 5.92mmol), and the solution was heated to reflux overnight. The mixture wasfiltered, and the filtrate was concentrated to dryness. The residue waspurified on a silica gel column (DCM/MeOH=20:1) to give the diol (250mg, 84%) as a white solid. The diol (130 mg, 0.21 mmol) in formic acid(5 mL) was stirred at 25° C. overnight. The solution was concentrationto dryness, and the residue in MeOH (30 mL) was stirred at 70° C.overnight. Completion of the reaction was determined by LCMS and HPLC.The solvent was removed, and the crude product was washed with EtOAc togive compound 49 (58 mg, 81%) as a white solid. ¹H NMR (DMSO-d₆, 400MHz) δ 10.73 (br, 1H), 7.98 (s, 1H), 6.58 (br, 2H), 6.08 (q, J=4.8, 9.2Hz, 2H), 5.64 (dt, J=5.6, 52.8 Hz, 1H), 5.40 (m, 1H), 4.52 (m, 1H),3.80-3.82 (m, 2H), 3.64 (q, 2H). ESI-MS: m/z 333.8 [M+H]⁺, 666.6[2M+H]⁺.

Example 40 Compound 50

Compound 50-1 (5.0 g, 8.5 mmol) and 6-chloropurine (3.0 g, 17.7 mmol)were co-evaporated with anhydrous toluene 3 times. To a stirredsuspension of 50-1 and 6-chloropurine in anhydrous MeCN (50 mL) wasadded DBU (7.5 g, 49 mmol) at 0° C. The mixture was stirred at 0° C. for15 mins, and TMSOTf (15 g, 67.6 mmol) was added dropwise at 0° C. Themixture was stirred at 0° C. for 15 mins until a clear solution formed.The mixture was heated to 70° C., and stirred overnight. The reactionwas monitored by LCMS. The mixture was cooled to RT, and diluted with EA(100 mL). The solution was washed with sat. NaHCO₃ solution and brine.The organic layer was dried over anhydrous Na₂SO₄, and concentrated atlow pressure. The residue was purified on silica gel column (EA in PEfrom 6% to 50%) to afford 50-2 (2.5 g, 46.3%) as a white foam.

Compound 50-2 (3.0 g, 4.8 mmol) was treated with NH₃ in MeOH (8 N, 20mL) in autoclave at 40-60° C. for 12 h. The mixture was evaporated atlow pressure, and the residue was purified on silica gel column (MeOH inEA from 0 to 10%) to give 50-3 (1.0 g, 71%) as a white foam.

To a solution of 50-3 (4.3 g, 14.8 mmol) in acetone/DMF (4/1, 40 mL) wasadded TsOH.H₂O (8.4 g, 0.044 mol) and 2,2-dimethoxypropane (30 g, 0.296mol), and the mixture stirred at 60-70° C. for 12 h. The mixture wasconcentrated at low pressure, and the residue was purified on silica gelcolumn (EA in PE from 50% to 100%) to give 50-4 (5.0 g, 83%).

To a solution of 50-4 (10.5 g, 31.7 mmol) in pyridine (50 mL) was addedTBSCl (5.3 g, 34.9 mmol), and the mixture stirred at RT for 12 h. Thesolvent was removed at low pressure, and the residue was dissolved inDCM (100 mL). The solution was washed with brine, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysilica gel column to provide 50-5 (8.4 g, 60%), which used withoutfurther purification.

Compound 50-5 (8.4 g, 18.8 mmol) was co-evaporated with pyridine. To astirred solution of 50-5 (8.4 g, 18.8 mmol) in pyridine (35 mL) wasadded MMTrCl (8.1 g, 26.4 mmol). The mixture was stirred at 30-40° C.for 12 h under N₂. The mixture was concentrated at a low pressure, andthe residue was dissolved in DCM (150 mL). The solution was washed withsaturated NaHCO₃ solution, dried over anhydrous Na₂SO₄, and concentratedat low pressure. The residue was purified on silica gel column (EA in PEfrom 10% to 20%) to provide 50-6 (10.8 g, 80%) as a solid

To a solution of 50-6 (11.5 g, 0.016 mol) in THF (100 mL) was added TBAF(4.62 g, 0.018 mol) at RT, and the mixture stirred for 4 h. The solventwas evaporated at low pressure, and the mixture was dissolved in DCM(150 mL). The solution was washed with brine, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified onsilica gel column (EA in PE from 50% to 100%) to afford 50-7 (8.8 g,91%). ESI-MS: m/z 604.4 [M+H]⁺.

To a solution of 50-7 (4.4 g, 7.3 mmol) in dioxane (50 mL) was added DCC(4.5 g, 21.9 mmol), DMSO (2.5 mL), TFA.Py (1.48 g, 7.65 mmol) at 0° C.The mixture was slowly warm to RT and stirred for 4 h. Completion of thereaction was determined by LCMS. The mixture was concentrated at lowpressure. The residue was purified on silica gel column to give 50-8(4.4 g, 7.3 mmol), which was used without further purification.

To a solution of 50-8 in dioxane (40 mL) was added water (20 mL), HCHO(37%, 7 mL) and NaOH (1N, 15 mL). The solution was stirred at RTovernight. The mixture was treated with NaBH₄ (1.1 g, 29.2 mmol) slowly,and stirred for 30 mins. The mixture was adjusted to pH=7-8 by slowaddition of HCl (1M) solution, and extracted with EA (150 mL). Thesolution was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified on silica gelcolumn to give 45-1 (3.0 g, 65%). ESI-MS: m/z 633.9 [M+H]⁺.

To a solution of 45-1 (1.5 g, 2.37 mmol) in anhydrous pyridine (30 mL)was added DMTrCl (3.6 g, 10.7 mmol) at −30° C. The mixture was stirredat RT overnight. The solution was quenched with MeOH, and concentratedat low pressure. The residue was purified by column chromatography togive 50-9 (3 g, 45%) as a yellow solid

To a solution of 50-9 (1.1 g, 1.18 mmol) in pyridine (10 mL) was addedimidazole (0.24 g, 3.53 mmol) and TBSCl (0.35 g, 2.35 mmol). The mixturewas stirred at RT for 12 h. The solvent was evaporated at low pressure,and the residue was dissolved in EA (50 mL). The solution was washedwith brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified on silica gel column (30% EA in PE)to afford 50-10 (0.83 g, 67%)

To a solution of 50-10 (1.1 g, 1.05 mmol) in DCM (12 mL) was addedCl₂CHCOOH (0.5 mL) at −70° C., and stirred for 1 h. The solution wastreated with Cl₂CHCOOH (1 mL) in DCM (10 mL) at −70° C., and the mixturewas stirred at −70˜−10° C. for 20 mins. Completion of the reaction wasdetermined by LCMS. The reaction was quenched with sat. NaHCO₃ solution,and extracted with DCM (3×40 mL). The organic phase was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified on silica gel column (EA in PE from 15% to 30%) to afford 50-11(0.58 g, 74%).

To a solution of 50-11 (200 mg, 0.268 mmol) and pyridine (53 mg, 0.67mmol) in anhydrous DCM (5 mL) was added Tf₂O (90 mg, 0.32 mmol) at −30°C. The mixture was stirred for 1 h, and slowly warmed to RT. Completionof the reaction was determined by TLC. The reaction was quenched withsat. NaHCO₃ solution, and extracted with DCM (3×30 mL). The organicphase was dried over anhydrous Na₂SO₄, and concentrated to dryness atlow pressure. Crude 50-12 (200 mg, 0.27 mmol) was used without furtherpurification.

To a solution of 50-12 (200 mg, 0.27 mmol) in DMF (5 mL) was added LiCl(45 mg, 1.07 mmol), and stirred at 30-40° C. for 12 h. The solvent wasevaporated at low pressure, and the residue was dissolved in DCM (10mL). The solution was washed with brine, dried over anhydrous Na₂SO₄,and concentrated at low pressure. Crude 50-13 was used without furtherpurification.

A mixture of 50-13 (245 mg, 0.32 mmol) and TBAF (200 mg, 0.7 mmol) inTHF was stirred at 30° C. for 1 h. The mixture was concentrated at a lowpressure, and the residue was dissolved in DCM (15 mL). The solution waswashed with brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified on silica gel column (EA in PE from2% to 50%) to provide 50-14 (150 mg, 72%). ESI-MS: m/z 652.3 [M+H]⁺.

Compound 50-14 (0.2 mmol) was dissolved in 50% TFA (10 mL) in methanol,and the mixture was kept at RT overnight. The solvent was evaporated andco-evaporated with methanol/toluene mixture to remove traces of acid.The residue was dissolved in 20% triethylamine in methanol, kept for 15mins and evaporated. The product was isolated by RP HPLC on Synergy 4micron Hydro-RP column (Phenominex). A linear gradient of methanol from0 to 60% in 50 mM triethylammonium acetate buffer (pH 7.5) was used forelution. The corresponding fractions were combined, concentrated andlyophilized 3 times to remove excess buffer. Compound 50 was obtained(45 mg, 67%). MS: m/z 338.0 [M−1].

Example 41 Compound 51

To a solution of 51-1 (12.3 g, 19.9 mmol) in DMF (50 mL) was added NaH(800 mg, 20 mmol) at 0° C. The mixture was stirred at RT for 3 h. Themixture was treated with CsF (30.4 g, 200 mmol), and then stirred at RTfor 3 h. The reaction was quenched with water, and extracted with EA.The organic layer was dried over anhydrous Na₂SO₄, and concentrated todryness at low pressure. The residue was purified on silica gel column(20% EA in PE) to give 51-2 (4.1 g, 61%) as a white solid.

To a solution of 51-2 (4.1 g, 12.1 mmol) in THF (120 mL) was added NaOHsolution (1N, 13 mL) at 0° C. The mixture was stirred at RT for 3 h. Thesolution was neutralized with 0.5 M HCl aq. to pH˜7. The mixture waspartitioned between EA and water. The organic layer was dried overanhydrous Na₂SO₄, and concentrated to dryness at low pressure. Theresidue was purified on silica gel column (30% EA in PE) to give 51-3(3.1 g, 72%) as a white solid. ESI-MS: m/z 379.1 [M+Na]⁺.

Compound 51-3 (0.2 mmol) was dissolved in 80% HCOOH (10 mL), and themixture was heated at 45° C. for 24 h. The solvent was evaporated andco-evaporated with methanol/toluene mixture to remove traces of acid.The residue was dissolved in 20% triethylamine in methanol, kept for 15mins and evaporated. Compound 51 (68%) was isolated by silica gelchromatography in gradient of methanol in DCM from 5% to 20%. MS: m/z289.0 [M−1].

Example 42 Compound 52

A mixture of 52-2 (1.2 g; 4 mmol) and NaI (0.6 g; 4 mmol) in acetone (13mL) was stirred at RT for 1 h. Compound 52-1 (1 g; 3 mmol) and K₂CO₃(2.07 g; 45 mmol) were added. The mixture was stirred at RT for 24 h.The precipitate was filtered, and the filtrate was evaporated.Purification of the residue on silica (25 g column) with hexanes/EtOAc(30-100% gradient) yielded 52-3 as a colorless foam (1.14 g; 64%).

To a solution of triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (2.3 mmol, prepared from ofbis(POC)phosphate (0.75 g) and Et₃N (0.32 mL)) in THF was added 52-3(1.14 g; 1.9 mmol). The mixture evaporated and rendered anhydrous byco-evaporating with pyridine follow by toluene. The residue wasdissolved in anhydrous THF (20 mL) and cooled down in an ice-bath.Diisopropylethylamine (1.0 mL; 2 eq.) was added, followed by BOP-Cl(0.72 g; 1.5 eq.) and 3-nitro-1,2,4-triazole (0.32 g; 1.5 eq.). The nmixture was stirred at 0° C. for 90 mins, diluted with EtOAc, washedwith sat. aq. NaHCO₃ and brine, and dried (Na₂SO₄). The residue waspurified on silica (25 g column) with CH₂Cl₂/i-PrOH (3-10% gradient) toyield (1.2 g, 70%) of 52-4.

A solution of 52-4 (1.2 g; 1.3 mmol) in 80% aq. HCOOH was stirred at RTfor 2 h, and then concentrated. The residue was co-evaporated withtoluene and then with MeOH containing small amount of Et₃N (2 drops).Purification on silica (25 g column) with CH₂Cl₂/i-PrOH (4-10% gradient)yielded 52-5 (0.96 g, 85%).

To a solution of 52-5 (0.52 g; 0.57 mmol) in EtOH (25 mL) were added HCl(4 N/dioxane; 0.29 mL, 2 eq.) and 10% Pd/C (25 mg). The mixture wasstirred under H₂ (normal pressure) for 1 h. The catalyst was removed byfiltration through a Celite pad, and the filtrate was evaporated toyield compound 52 as its HCl salt (4.2 g; 96%). MS: m/z=732 [M+1].

Example 43 Compound 53

Compound 53-2 (0.20 g, 64%) was prepared in the same manner from 53-1(0.16 g; 0.49 mmol) and triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.74 mmol) with DIPEA (0.34mL), BopCl (250 mg), and 3-nitro-1,2,4-triazole (112 mg) in THF (5 mL)following the procedure for the preparation of 52-4.

A solution of 53-2 (0.20 g; 0.31 mmol) in 80% aq. HCOOH was stirred atRT for 2 h, and then concentrated. The residue was co-evaporated withtoluene and then with MeOH containing small amount of Et₃N (2 drops).Purification on silica gel (10 g column) with CH₂Cl₂/MeOH (4-10%gradient) was followed by RP-HPLC purification in 5 runs on a SynergiHydro RP column 250×30 mm (Phenomenex P/N 00G-4375-U0-AX) using H₂O andACN both 50 mM TEAA. Gradient was 25-75% ACN in 20 mins at 24 mL/mins,254 nM detection. The product eluted at 16.0 mins. Pure fractions werepooled and lyophilized. TEAA was removed by dissolving the product inDMSO (2 mL) and injecting the product on the same column using only H₂Oand ACN. Pure fractions were pooled and lyophilized to produce compound53 (18 mg). MS: m/z=1197 (2M+1).

Example 44 Compound 54

Chloromethyl chloroformate (112 mmol; 10.0 mL) was added to an icecooled solution of 2-methoxyethanol (97 mmol; 7.7 mL) in dichloromethane(DMC) (100 mL) followed by pyridine (9.96 mL) at 0° C. After stirringovernight at RT, the mixture was washed twice with 0.5 M HCl, followedby water and aqueous sodium bicarbonate. The mixture was dried overmagnesium sulfate, filtered, evaporated in vacuo and distillation invacuo to afford 54-2 as a colorless oil (13.0 g).

Compound 54-2 (5.7 g) was added to a solution of sodium iodide (21.07 g)in acetone (45 mL). After 20 stirring at 40° C. for 2.5 h, the mixturewas cooled in ice, filtered and evaporated in vacuo. The residue wastaken up in dichloromethane, washed with aqueous sodium bicarbonate andsodium thiosulfate, dried over magnesium sulfate, filtered andevaporated in vacuo to give 54-3 as a light yellow oil of 54-3 (8.5 g),which was used without further purification.

A mixture of phosphoric acid (crystal, 2.4 g) and triethylamine (6.6 mL)in benzyl alcohol (13 g; 12.5 mL) was stirred at RT until the phosphoricacid was completely dissolved. Trichloroacetonitrile (17.2 g; 11.94 mL)was added, and the mixture was stirred at RT for 18 h. The solvent andexcess trichloroacetonitrile were removed under reduced pressure. Theresidue was dissolved in water (about 200 mL), and the aqueous solutionwashed with ether (3×50 mL). Benzylphosphoric acid (triethylamine salt)was obtained after lyophilization as a yellowish semi-solid (7.15 g). Asolution of benzylphosphoric acid (TEA salt, 1.6 g) in MeOH (90 mL) andwater (30 mL) was treated with Dowex 50WX2-400 (“153 mL” settled resin)at RT for 18 h. The resin was removed by filtration, and silvercarbonate powder (1.25 g) was added to the filtrate. After thesuspension was heated at 80° C. for 1 h, all solvent was removed underreduced pressure to dryness. The solid was used without furtherpurification.

Dry acetonitrile (25 mL) was added to benzylphosphoric acid (silversalt) followed by addition of 54-3 (3.12 g; 12 mmol). The suspension wasstirred at RT overnight. After the solid was removed by filtration, theproduct was purified by silica gel chromatography using hexane/ethylacetate (3:1 v/v) as the eluent to give 54-4 as a colorless liquid (860mg, 50%).

Compound 54-4 (750 mg; 1.65 mmol) was dissolved in methanol (10 mL).Pd-on-carbon (85 mg) and TEA (1 eq.) were added. The flask was chargedwith hydrogen gas for 1 h. The catalyst was filtered, and the solventremoved in vacuo to give 54-5 (triethylammonium salt) (510 mg) which wasused immediately without further purification.

Compound 54-6 (320 mg; 0.9 mmol) and 54-5 (510 mg, 1.35 mmol; 1.5×) wereco-evaporated twice with pyridine and twice with toluene. Compounds 54-5and 54-6 were dissolved in THF (8 mL) at 0° C. Diisopropylethylamine(DIPEA) (0.62 mL; 4 eq.), bis(2-oxo-3-oxazolidinyl)phosphinic chloride(Bop-Cl) (0.45 g; 2 eq.), nitrotriazole (0.2 g, 2 eq.) were added. Themixture was kept at 0° C. for 2 h and then diluted with EA (50 mL). Themixture was then extracted with sat. sodium bicarbonate (2×50 mL) anddried over sodium sulfate. The solvents were removed in vacuo. Theresidue was purified by flash chromatography using a 10 to 100% gradientof EA in hexane to give purified 54-7 (430 mg, 0.6 mmol).

Purified 54-7 was dissolved in 80% aq. HCOOH (20 mL) and kept at 45° C.for 18 h. After cooling to RT, the solvent was removed in vacuo. Theresidue co-evaporated with toluene (3×25 mL). The residue was purifiedby flash chromatography using a 0 to 20% gradient of methanol in DCM togive purified compound 54 (200 mg, 0.3 mmol). ¹H-NMR (CDCl₃): δ 9.28 (s,1H), 7.54 (d, 1H), 5.95 (s, 1H), 5.65-5.81 (m, 5H), (d, 2H), 4.76 (dd,2H), 4.44-4.46 (m, 1H), 4.35-4.40 (m, 5H), 4.22 (2H), 4.04 (1H), 3.65(t, 4H), 3.39 (6H), 1.8 (s, 1H), 1.24 (s, 3H). ³¹P-NMR (CDCl₃): δ −4.09ppm.

Example 45 Compound 55

Compound 55-2 (158 mg, 50%) was prepared from 55-1 (0.21 g; 0.35 mmol)and triethylammonium bis(isopropyloxycarbonyloxymethyl)phosphate (0.54mmol) with DIPEA (0.18 mL), BopCl (178 mg), and 3-nitro-1,2,4-triazole(80 mg) in THF (4 mL).

A solution of 55-2 (158 mg) in acetonitrile (1 mL) and HCl (4 N/dioxane;85 μL) was stirred at RT for 30 mins. The reaction was quenched withMeOH and concentrated. The residue was purified on silica gel (10 gcolumn) with CH₂Cl₂/i-PrOH (3-10% gradient) to give compound 55 (85 mg,76%). MS: m/z=656 [M+1].

Example 46 Compound 56

To a solution of 49-3 (300 mg, 0.4 mmol) and pyridine (80 mg, 1.0 mmol)in DCM (5 mL) was added Tf₂O (136 mg, 0.48 mol) in a solution of DCM (1mL) dropwise at −30° C. The mixture was stirred at −30° C. to 0° C. for20 mins. The reaction was quenched with water, and extracted with DCM(20 mL). The organic phase was dried over anhydrous Na₂SO₄, andevaporated to give crude 56-1 (352.8 mg, 0.4 mmol), which was usedwithout further purification.

To a solution of 56-1 (352.8 mg, 0.4 mmol) in DMF (5 mL) was added NaI(480 mg, 3.2 mmol). The mixture was stirred at 30° C. for 10 h. Thereaction was quenched with water, and extracted with DCM (20 mL). Theorganic phase was dried over anhydrous Na₂SO₄, and concentrated todryness at low pressure. The residue was purified by prep-TLC (30% EA inPE) to give 56-2 (270 mg, 31%).

To a solution of 56-2 (600 mg, 0.7 mmol) in anhydrous toluene (30 mL)was added AIBN (34 mg, 0.21 mmol) and Bu₃SnH (307.7 mg, 1.05 mmol) intoluene (10 mL). The mixture was bubbled with N₂ for 30 mins, and heatedto 135° C. for 2 h. The mixture was treated with sat. aq. CsF, and thenstirred for 2 h. The mixture was diluted with EA (100 mL). The organicphase was washed with brine, dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The residue was purified on a silica gelcolumn (10% EA in PE) to give 56-3 and a by-product (400 mg, 72%).

A mixture of 56-3 (400 mg, 0.55 mmol) in 90% TFA (10 mL) was stirred at50° C. for 4 h. The reaction was monitored by LCMS. The mixture wastreated with MeOH (5 mL), and concentrated under reducing pressure. Theresidue was purified by prep-HPLC to give compound 56 (46 mg, 27%).ESI-MS: m/z 306.1 [M+H]⁺.

Example 47 Compound 57

Compound 57-2 (120 mg, 72%) was prepared in the same manner from 57-1(0.11 g; 0.18 mmol) and triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.35 mmol) with DIPEA (0.15mL), BopCl (114 mg), and 3-nitro-1,2,4-triazole (51 mg) in THF (2.5 mL)using the method as described for 52-4 from 52-3.

Compound 57 (14 mg, 77%) was prepared from 57-2 (25 mg) in acetonitrile(0.1 mL) and 4 N HCl/dioxane (8 μL) using the method as described forcompound 55. MS: m/z=658 [M+1].

Example 48 Compound 60

To a stirred solution of uracil (21 g, 188 mmol) in anhydrous MeCN (200mL) was added BSA (110 g, 541 mmol), and the mixture was refluxed for 2h. The mixture was then cooled to RT and treated with 60-1 (55 g, 93.2mmol) and TMSOTf (145 g, 653 mmol). The mixture was refluxed overnight.After the starting material disappeared, the reaction was quenched withsat. NaHCO₃ solution, and extracted with EA. The organic layer was driedover anhydrous Na₂SO₄, and concentrated to dryness at low pressure. Theresidue was purified on silica column gel (20% EA in PE) to give 60-2(38 g, 70%) as a white sold.

Compound 60-2 (35 g, 0.06 mol) was treated with NH₃ in MeOH (7N, 200 mL)at RT. The mixture was stirred for 24 h at RT. Completion of thereaction was determined by LCMS. The mixture was concentrated at a lowpressure, and the residue was washed with DCM to give 60-3 (13 g, 81%)as a white solid.

To a solution of cyclopentanone (6 g, 8.33 mmol), and trimethoxymethane(8 mL) in MeOH (60 mL) was added TsOH (1.35 g, 7.1 mmol) at RT, and themixture was stirred 2 h. The resulting was quenched with NaOMe (0.385 g,7.12 mmol), and extracted with n-hexane (30 mL). The organic layer wasdried over anhydrous Na₂SO₄, and concentrated at low pressure to give1,1-dimethoxycyclopentane. To a solution of 60-3 (30 g, 0.11 mol) and1,1-dimethoxy cyclopentane (57 g, 0.44 mol) in 1,2-dichloroethane (200mL) was added TsOH (2.1 g, 0.011 mol), and the mixture was heated to 60°C. overnight. The reaction was quenched with triethylamine, andconcentrated to dryness at low pressure. The residue was washed withMeOH to give 60-4 (30 g, 82%).

To a solution of 60-4 (10 g, 30 mmol) in anhydrous CH₃CN (100 mL) wasadded IBX (8.4 g, 30 mmol, 1.05 eq.) at RT. The mixture was refluxed for12 h., and then cooled to 0° C. The precipitate was removed byfiltration, and the filtrate was concentrated to give crude 60-5 (10 g,100%) as a yellow solid.

Crude 60-5 (10 g, 30 mmol) was dissolved in 1,4-dioxane (100 mL). 37%HCHO (10 mL) and 2N NaOH aqueous solution (20 mL) were added at RT. Themixture was stirred at RT overnight, and adjusted to pH=7. The mixturewas treated with NaBH₄ (4.44 g, 120 mmol) at 0° C. The reaction wasstirred at RT for 30 mins and then quenched with sat. aq. NH₄Cl. Themixture was extracted with EA. The organic layer was dried over Na₂SO₄,and concentrated to dryness at low pressure. The residue was purified bysilica gel column chromatography (1-3% MeOH in DCM) to give 60-6 (5.5 g,50%) as a white solid.

To a stirred solution of 60-6 (5.0 g, 13.8 mmol) and pyridine (5 mL) inDCM (20 mL) was added Tf₂O (8.5 g, 30.3 mmol) dropwise at −70° C. Thesolution was warmed to 0° C. slowly, stirred at 0° C. for 0.5 h, andwashed with HCl (0.5 M). The DCM layer was concentrated to dryness atlow pressure, and the residue was purified on silica gel column to give60-7 (4.5 g, 52%) as a white solid.

To a solution of 60-7 (3.0 g, 4.8 mmol) in MeCN (10 mL) was added TBAF(5.0 g, 19.2 mmol). The reaction was allowed to proceed overnight. Thereaction was monitored by HPLC and LCMS. Aqueous sodium hydroxide (1N˜2eq.) was added, and the solution was stirred for 1 h. The mixture waspartitioned between sat. ammonium chloride solution and EA. The organiclayer was separated, and concentrated under reduced pressure.

The crude product was purified on silica gel column to give 60-8 (0.8 g,46%) as a white solid. ESI-MS: m/z 367.0 [M+H]⁺, 389.0 [M+Na]⁺.

Compound 60-8 (0.2 mmol) was dissolved in 80% HCOOH (10 mL), and themixture was heated at 45° C. for 24 h. The solvent was evaporated andco-evaporated with methanol/toluene mixture to remove traces of acid.The residue was dissolved in 20% triethylamine in methanol, kept for 15mins and evaporated. Compound 60 (65-68%) was isolated by silica gelchromatography in gradient of methanol in DCM from 5% to 20%. MS: m/z321.0 [M−1].

Example 49 Compound 63

A mixture of compound 45 (30 mg, 0.09 mmol), PTSA monohydrate (18 mg, 1eq.), and trimethyl orthoformate (0.3 mL; 30 eq.) in dioxane (1 mL) wasstirred 1 d at RT. The reaction was neutralized with NH₃/MeOH and thenfiltered. The filtrate was dissolved in a mixture of THF (0.5 mL) and80% aq. AcOH (0.25 mL). The solution kept for 1 h at RT, and thenevaporated. The residue was purified on silica gel (10 g column) withCH₂Cl₂/MeOH (4-15% gradient) to yield 63-1 (30 mg, 91%).

Compound 63-2 (28 mg, 52%) was prepared in the same manner from 63-1 (30mg, 0.08 mmol) and triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.12 mmol) with DIPEA (56μL), BopCl (40 mg), and 3-nitro-1,2,4-triazole (18 mg) in THF (1 mL)using the method for preparing 52-4 from 52-3. Purification was donewith CH₂Cl₂/MeOH (4-10% gradient).

Compound 63 (15 mg, 67%) was prepared from 63-2 (24 mg) using the methodfor preparing 52-5. Purification was done with CH₂Cl₂/MeOH (4-10%gradient). MS: m/z=636 [M+1].

Example 50 Compound 64

Compound 64-1 (8 mg, 40%) was prepared from compound 50 (17 mg) andtrimethylorthoformate (0.15 mL) with PTSA monohydrate (9 mg) in dioxane(0.5 mL) in the same manner as 63-1.

Compound 64-2 (10 mg, 72%) was prepared in the same manner from 64-1 (8mg, 0.02 mmol) and triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.036 mmol) with DIPEA (14μL), BopCl (10 mg), and 3-nitro-1,2,4-triazole (5 mg) in THF (0.4 mL) inthe same manner as 63-2.

Compound 64 (15 mg, 67%) was prepared from 64-2 (24 mg) in the samemanner as 63. MS: m/z=652 [M+1].

Example 51 Compound 65

Commercially available chloromethyl methyl carbonate (5.0 g) was treatedwith NaI to give 65a (5.38 g). Benzylphosphate (silver salt) and 65awere reacted to yield purified 65b (1.5 g) as described for compound 54.¹H-NMR (CD₃CN): δ 7.39-7.42 (m, 5H), 5.60 (d, 4H), 5.11 (d, 2H), 3.8 (s,6H). ³¹P-NMR (CD₃CN): δ −4.47 ppm. Compound 65b (415 mg; 1.7 mmol) wasdeprotected to give 65-1 (triethylammonium salt) (510 mg), which wasused immediately without further purification. Compound 54-6 (320 mg;0.9 mmol) and 65-1 (510 mg) were reacted to purified 65-2 (400 mg).Compound 65-2 (230 mg) was deprotected to give purified compound 65 (250mg). The aforementioned reactions were conducted using a methoddescribed in the preparation of compound 54. ¹H-NMR (CDCl₃): δ 9.00 (s,1H), 7.55 (d, 1H), 5.93 (s, 1H), 5.81 (d, 1H), 5.66-5.75 (m, 4H), 4.76(dd, 2H), 4.37-4.46 (m, 2H), 4.15 (d, 2H), 3.86 (t, 6H), 3.70 (d, 6H),1.65 (s, 6H), 1.25 (s, 3H). ³¹P-NMR (CDCl₃): δ −4.13 ppm.

Example 52 Compound 66

Compound 66a was prepared from 1,3-dimethoxypropan-2-ol. ¹H-NMR (CDCl₃)δ 5.73 (s, 2H), 5.03-5.06 (m, 1H), 3.59 (d, 4H), 3.38 (s, 6H). Dry ACN(25 mL) was added to benzylphosphate (silver salt) (5 mmol) followed byaddition of 66a (3.12 g; 12 mmol). The suspension was heated at 60° C.for 18 h. After the solid was removed by filtration, the product waspurified by silica gel chromatography using hexane/EA (3:1) as theeluent to provide 66b as a colorless liquid (540 mg, 50%). ¹H-NMR(CD₃CN): δ 7.39-7.42 (m, 5H), 5.61 (d, 4H), 5.10 (d, 2H), 4.97-5.01 (m,2H), 3.50-3.52 (m, 8H), 3.30 (s, 6H), 3.28 (s, 6H). ³¹P-NMR (CD₃CN): δ−4.42 ppm. Compound 66b (540 mg; 1.0 mmol) was deprotected to give 66-1(triethylammonium salt), which was used immediately without furtherpurification. Compound 54-6 (285 mg; 0.8 mmol) and 66-1 were reacted togive purified 66-2 (300 mg). Compound 66-2 (300 mg) was deprotected togive purified compound 66 (290 mg). The aforementioned reactions wereconducted using a method described in the preparation of compound 54.¹H-NMR (CDCl₃): δ 9.35 (s, 1H), 7.56 (d, 1H), 6.1 (s, 1H), 5.66-5.82 (m,5H), 5.04 (s, 1H), 4.76 (dd, 2H), 4.60 (d, ½H), 4.37-4.48 (m, 2H), 4.22(d, 2H), 4.06 (s, 1H), 3.58 (s, 8H), 3.57 (s, 12H), 1.93 (s, 1H), 1.23(s, 3H). ³¹P-NMR (CDCl₃): δ −4.08 ppm.

Example 53 Compound 67

Compound 67-1 (180 mg, 62%) was prepared in the same manner from 54-6(0.18 g, 0.5 mmol) and triethylammonium bis(acetyloxymethyl)phosphate(1.0 mmol) with DIPEA (0.35 mL), BopCl (0.25 g), and3-nitro-1,2,4-triazole (0.11 g) in THF (1 mL) using a method asdescribed for compound 44. Purification was done with CH₂Cl₂/i-PrOH(4-10% gradient).

Compound 67 (60 mg, 78%) was prepared from 67-1 (85 mg) using a methodas described for compound 44. MS: m/z=1027 (2M−1).

Example 54 Compound 68

To a solution of 68-1 (15 g, 50.2 mmol) in anhydrous pyridine (180 mL)was added BzCl (23.3 g, 165.5 mmol) at 0° C. under nitrogen. The mixturewas stirred overnight at RT. The mixture was diluted with EA and washedwith NaHCO₃ aq. solution. The organic layer was dried with anhydrousNa₂SO₄, and concentrated to dryness. The organic layer was dried andconcentrated to give a residue, which was purified by silica gel columnchromatography (15% EtOAc in PE) to give 68-2 (27 g, 93.5%) as a whitesolid.

Compound 68-2 (27 g, 47 mmol) was dissolved in 90% HOAc (250 mL) andheated to 110° C. The mixture was stirred overnight at 110° C. Thesolvent was removed and diluted with EA. The mixture was washed withNaHCO₃ aq. solution and brine. The organic layer was dried andconcentrated to give crude 68-3.

Compound 68-3 was dissolved in NH₃/MeOH (600 mL) and stirred overnight.The solvent was concentrated to give the residue, which was purified bysilica gel column chromatography (5% MeOH in DCM) to give 68-4 (12 g,99%) as a white solid.

To a solution of 68-4 (15 g, 56.8 mmol) in anhydrous pyridine (200 mL)was added imidazole (7.7 g, 113.6 mmol) and TBSCl (9.4 g, 62.5 mmol) atRT. The mixture was stirred overnight. And the solvent was removed anddiluted with EA. The mixture was washed with NaHCO₃ aq. solution andbrine. The organic layer was dried and concentrated to give crude 68-5.

To a solution of 68-5 in anhydrous DCM (200 mL) was added collidine (6.8g, 56.8 mmol), MMTrCl (17.8 g, 56.8 mmol) and AgNO₃ (9.6 g, 56.8 mmol)at RT. The mixture was stirred overnight. The mixture was filtered, andthe filtrate was washed with NaHCO₃ aq. solution and brine. The organiclayer was dried over Na₂SO₄, and concentrated at low pressure to givethe residue, which was purified by silica gel column chromatography (5%EA in PE) to give 68-6 (32 g, 87%).

Compound 68-6 (32 g, 49.2 mmol) was dissolved in a solution of TBAF inTHF (1M, 4 eq.) at RT. The mixture was stirred overnight, and thesolvent was removed. The mixture was diluted with EA and washed withwater. The organic layer was dried and concentrated to give the crudeproduct, which was purified by silica gel column chromatography (33% EAin PE) to give 68-7 (21 g, 79%).

To a solution of 68-7 (21 g, 38.8 mmol) in DCM (200 mL) was addedpyridine (9.2 mL, 116.4 mmol). The solution was cooled to 0° C. andDess-Martin periodinane (49 g, 116.4 mmol) was added in a singleportion. The mixture was stirred for 4 h at RT. The reaction wasquenched with Na₂S₂O₃ solution and sodium bicarbonate aqueous solution.The mixture was stirred for 15 mins. The organic layer was separated,washed with diluted brine and concentrated under reduced pressure. Theresidue was dissolved in dioxane (200 mL), and the solution was treatedwith 37% aqueous formaldehyde (20 mL, 194 mmol) and 2 N aqueous sodiumhydroxide (37.5 mL, 77.6 mmol). The mixture was stirred at RT overnightand NaBH₄ (8.8 g, 232.8 mmol) was added. After stirring for 0.5 h at RT,the excess of aqueous sodium hydroxide was removed with ice water. Themixture was diluted with EA. The organic phase was washed with brine,dried over magnesium sulfate and concentrated at low pressure. Theresidue was purified by column chromatography (4% MeOH in DCM) to give68-8 (10 g, 50.5%) as a white foam.

Compound 68-8 (4.8 g, 8.5 mmol) was co-evaporated with toluene twice.The residue was dissolved in anhydrous DCM (45 mL) and pyridine (6.7 g,85 mmol). The solution was cooled to 0° C. and triflic anhydride (4.8 g,18.7 mmol) was added dropwise over 10 mins. At this temperature, thereaction was stirred for 40 mins. TLC (50% EA in PE) showed that thereaction was complete. The mixture was purified by column chromatography(EA in PE from 0 to 20%) to give 68-9 (6.1 g, 86.4%) as a brown foam.

Compound 68-9 (6.1 g, 7.3 mmol) was dissolved in MeCN (25 mL). Themixture was treated with a solution of TBAF in THF (1M, 25 mL) at RT.The mixture was stirred overnight. TBAF in THF (1M, 15 mL) was added andstirred for 4 h. The mixture was treated with aqueous sodium hydroxide(1N, 14.6 mmol) and stirred for 1 h. The reaction was quenched withwater (50 mL) at 0° C. and extracted with EA. The organic layer wasdried and concentrated to give the crude product, which was purified bysilica gel column chromatography (50% EA in PE) to give 68-10 (2.1 g,50.6%).

To a solution of 68-10 (1.5 g, 2.6 mmol) in anhydrous pyridine (15 mL)was added imidazole (530 mg, 7.8 mmol) and TBSCl (585 mg, 3.9 mmol) atRT. The mixture was stirred for 2 h. The solvent was removed and dilutedwith EA. The mixture was washed with NaHCO₃ aq. solution and brine. Theorganic layer was dried and concentrated to give the residue, which waspurified by silica gel column chromatography (10% EA in PE) to give68-11 (1.5 g, 84.5%).

To a solution of 68-11 (1.5 g, 2.2 mmol) in anhydrous CH₃CN (11 mL) wereadded DMAP (671 mg, 5.5 mmol), TEA (555 mg, 5.5 mmol) and TPSCl (1.66 g,5.5 mmol) at RT. The reaction was stirred overnight at RT. NH₄OH (10 mL)was added, and the mixture was stirred for 2 h. The mixture was dilutedwith EA and washed with NaHCO₃ solution. The organic layer was dried andconcentrated at low pressure. The residue was purified by silica gelcolumn chromatography (2% MeOH in DCM) to give crude 68-12, which waspurified by prep-TLC to give 68-12 (1.2 g, 80%) as a white solid.

A solution of 68-12 (1.2 g, 1.76 mmol) in 80% HCOOH (60 mL) was stirredfor 4 h. The solvent was removed at low pressure. The crude product wasdissolved in MeOH (40 mL) and stirred overnight. The solvent wasconcentrated to give the crude product, which was purified by columnchromatography on silica gel (MeOH in DCM 10%) to give compound 68 (480mg, 92%) as a white solid. ESI-MS: m/z 591 [2M+H]⁺.

Example 55 Compound 69

A solution of 68-8 (2.63 g, 4.64 mmol) in anhydrous pyridine/DCM at 0°C. was added Tf₂O (3.27 g, 11.59 mmol). The mixture was stirred at RTfor 40 mins. The solvent was removed at reduced pressure, and theresidue was purified by column chromatography to give 69-1 (2.60 g,67%).

A solution of 69-1 (2.65 g, 3.19 mmol) in anhydrous DMF was added sodiumhydride (153 mg, 3.82 mmol) at 0° C. for 1 h. The solution was used forthe next step without purification. The solution was treated with LiCl(402 mg, 9.57 mmol) at RT. The mixture was stirred at RT for 12 h. Thereaction was quenched with saturated ammonium chloride solution, andextracted with EA. The organic layers were dried over Na₂SO₄, andconcentrated at low pressure to give crude 69-2.

To a solution 69-2 (1.81 g, 3.19 mmol) in anhydrous THF (20 mL) wasadded 1 N NaOH (4 mL, 3.83 mmol) at RT. The mixture was stirred at RTfor 2 h. The reaction was quenched with saturated sodium bicarbonatesolution, and extracted with EA. The organic phase was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by column chromatography to give 69-3. (1.34 g, 72%).

A solution of 69-3 (925 mg, 1.58 mmol) in dichloromethane (10 mL) wasadded TBSCl (713 mg, 4.75 mmol) and imidazole (323 mg, 4.74 mmol), andstirred at RT overnight. The mixture was diluted with EA (20 mL), andwashed with brine. The organic phase was concentrated at low pressure togive the crude product. The residue was purified by columnchromatography to give 69-4 (1.0 g, 90%).

A solution of 69-4 (1.24 g, 1.78 mmol) in anhydrous acetonitrile (10 mL)was added TPSCl (1.34 g, 4.45 mmol), DMAP (543 mg, 4.45 mmol) and TEA(450 mg, 4.45 mmol), and the mixture was stirred at RT for 3 h. Thesolvent was removed under reduced pressure, and the residue wasdissolved in EA (30 mL). The solution was washed with brine, dried withanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified on silica gel to give 69-5 (1.0 g, 81%) as a white solid.

Compound 69-5 (1.0 g, 1.43 mmol) was treated with 80% HCOOH (10 mL), andstirred at RT overnight. The solvent was removed under reduced pressure,and the residue was purified on silica gel using 5% MeOH in CH₂Cl₂ togive compound 69 (264 mg, 60%). ESI-MS: m/z 311.9 [M+H]⁺.

Example 56 Compound 70

Benzylphosphate (silver salt) and commercially available chloromethylisobutylrate (5.0 g) yielded purified 70a (3.84 g). ¹H-NMR (CD₃CN): δ7.39-7.42 (m, 5H), 5.60 (d, 4H), 5.09 (d, 2H), 1.94-1.96 (m, 2H),1.12-1.17 (m, 12H). ³¹P-NMR (CD₃CN): δ −4.03 ppm. Compound 70a (780 mg;2.0 mmol) was deprotected to give 70-1 (triethylammonium salt), whichwas used immediately without further purification. Compound 54-6 (356mg; 1.0 mmol) and 70-1 were reacted to give purified 70-2 (230 mg).Compound 70-2 (230 mg) was deprotected to yield purified compound 70 (80mg, 0.14 mmol). The aforementioned reactions were conducted using amethod described in the preparation of compounds 54 and 66. ¹H-NMR(CDCl₃): δ 8.25 (s, 1H), 7.55 (d, 1H), 5.93 (s, 1H), 5.81 (d, 1H),5.66-5.75 (m, 4H), 4.76 (dd, 2H), 4.37-4.46 (m, 2H), 4.15 (d, 2H), 3.86(t, 6H), 3.70 (d, 6H), 1.65 (s, 6H), 1.25 (s, 3H). ³¹P-NMR (CDCl₃): δ−4.41 ppm.

Example 57 Compound 71

Compound 71-2 (0.34 g, 60%) was prepared from 52-1 (0.33 g) and 71-1(0.34 g) in acetone (6 mL) with NaI (0.19 g) and K₂CO₃ (0.69 g).

Compound 71-3 (0.28 g, 74%) was prepared in the same manner from 71-2(0.25 g, 0.45 mmol) and triethylammoniumbis(ethoxycarbonyloxymethyl)phosphate (0.9 mmol) with DIPEA (0.35 mL),BopCl (0.25 g), and 3-nitro-1,2,4-triazole (0.11 g) in THF (5 mL).Purification was done with hexanes/EtOAc (30-100% gradient).

A solution of 71-3 (0.28 g, 0.33 mmol) in 80% aq. AcOH was heated at 45°C. for 4 h and then concentrated. The residue was coevaporated withtoluene and then with MeOH containing small amount of Et₃N (2 drops).Purification on silica gel (10 g column) with CH₂Cl₂/i-PrOH (4-10%gradient) yielded 71-4 (0.22 g, 84%).

To a solution of 71-4 (148 mg, 0.18 mmol) in EtOAc (0.6 mL) at 0° C. wasadded 4 N HCl/dioxane (0.5 mL), and the mixture kept at RT for 1 h.Ether was added and compound 71 precipitated. The mixture was filteredand washed with ether to give compound 71 (100 mg, 75%). Theaforementioned reactions were conducted using a method described in thepreparation of compound 52. MS: m/z=704 [M+1].

Example 58 Compound 33

Compound 33-1 (50 g, 86.0 mmol) and 6-Cl-guanine (16.1 g, 98.2 mmol)were co-evaporated with anhydrous toluene 3 times. To a solution of 33-1(50 g, 86.0 mmol) and 6-Cl-guanine (16.1 g, 98.2 mmol) in MeCN (200 mL)was added DBU (39.5 g, 258.0 mmol) at 0° C. The mixture was stirred at0° C. for 30 mins, and TMSOTf (95.5 g, 430.0 mmol) was added dropwise at0° C. The mixture was stirred at 0° C. for 30 mins until a clearsolution was observed. The mixture was heated to 70° C., and stirredovernight. The solution was cooled to RT, and diluted with EA (100 mL).The solution was washed with sat. NaHCO₃ solution and brine. The organiclayer was dried over Na₂SO₄, and concentrated at low pressure. Theresidue was purified by column on silica gel (EA in PE from 10% to 40%)to give 33-2 (48.0 g, 88.7%) as a yellow foam. ESI-MS: m/z 628 [M+H]⁺.

To a solution of 33-2 (48.0 g, 76.4 mol), AgNO₃ (50.0 g, 294.1 mmol) andcollidine (40 mL) in anhydrous DCM (200 mL) was added MMTrCl (46.0 g,149.2 mmol) in small portions under N₂. The mixture was stirred at RTfor 3 h under N₂. Completion of the reaction was determined by TLC.After filtration, the filtrate was washed with sat. NaHCO₃ solution andbrine. The organic layer was dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn (EA in PE from 5% to 50%) to the give crude 33-3 (68 g, 98%).ESI-MS: m/z 900.1 [M+H]⁺.

Sodium (8.7 g, 378.0 mmol) was dissolved in dry EtOH (100 mL) at 0° C.,and slowly warmed to RT. Compound 33-3 (68.0 g, 75.6 mmol) was treatedwith freshly prepared NaOEt solution, and stirred overnight at RT.Completion of the reaction was determined by TLC and LCMS. The mixturewas concentrated at a low pressure, diluted with H₂O (100 mL), andextracted with EA (3×100 mL). The organic layer was dried over anhydrousNa₂SO₄, and evaporated at low pressure. The residue was purified bysilica gel column chromatography (MeOH in DCM from 1% to 5%) to give33-4 (34.0 g, 75.2%) as a yellow solid. ESI-MS: m/z 598 [M+H]⁺.

Compound 33-4 (32.0 g, 53.5 mmol) was co-evaporated with anhydrouspyridine 3 times. To an ice cooled solution of 33-4 (32.0 g, 53.5 mmol)in anhydrous pyridine (100 mL) was added a solution of TsCl (11.2 g,58.9 mmol) in pyridine (50 mL) dropwise at 0° C. The mixture was stirredfor 18 h. at 0° C. The reaction was monitored by LCMS, and quenched withH₂O. The solution was concentrated at low pressure, and the residue wasdissolved in EA (100 mL), and washed with sat. NaHCO₃ solution. Theorganic layer was dried over anhydrous Na₂SO₄, and evaporated at a lowpressure. The residue was purified by silica gel column chromatography(MeOH in DCM from 1% to 5%) to give crude 33-5 (25.0 g, 62.2%) as ayellow solid. ESI-MS: m/z 752 [M+H]⁺.

To a solution of 33-5 (23.0 g, 30.6 mmol) in acetone (150 mL) was addedNaI (45.9 g, 306.0 mmol) and TBAI (2.0 g), and the mixture was refluxedovernight. Completion of the reaction was determined by LCMS. Themixture was concentrated at low pressure, and the residue was dissolvedin EA (100 mL). The solution was washed with brine, and dried overanhydrous Na₂SO₄. The organic solution was evaporated at low pressure,and the residue was purified by silica gel column chromatography (DCM:MeOH=100:1 to 20:1) to give a crude product. To a solution of the crudeproduct in dry THF (200 mL) was added DBU (14.0 g, 91.8 mmol), and themixture was heated to 60° C. and stirred overnight. The reaction wasmonitored by LCMS. The reaction was quenched with sat. NaHCO₃ solution,and the solution was extracted with EA (100 mL). The organic layer wasdried over anhydrous Na₂SO₄, and evaporated at low pressure. The residuewas purified by silica gel column chromatography (MeOH in DCM from 1% to5%) to give 33-6 (12.0 g, 67.4%) as a yellow solid. ESI-MS: m/z 580[M+H]⁺.

To an ice cooled solution of 33-6 (8.0 g, 13.8 mmol) in anhydrous MeCN(100 mL) was added NIS (3.9 g, 17.2 mmol) and TEA.3HF (3.3 g, 20.7 mmol)at 0° C. The mixture was stirred at RT for 18 h, and the reaction waschecked by LCMS. After the reaction was completed, the reaction wasquenched with sat. Na₂SO₃ solution and sat. NaHCO₃ solution. Thesolution was extracted with EA (3×100 mL). The organic layer was driedover anhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (EA in PE from 10% to 50%)to give 33-7 (7.2 g, 72.0%) as a solid. ESI-MS: m/z 726 [M+H]⁺.

To a solution of 33-7 (7.2 g, 9.9 mmol) in dry DCM (100 mL) was addedDMAP (3.6 g, 29.8 mmol), and BzCl (2.8 g, 19.8 mmol) at 0° C. Themixture was stirred overnight, and checked by LCMS. The mixture waswashed with sat. NaHCO₃ solution. The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (EA in PE from 10% to 30%)to give 33-8 (8.0 g, 86.4%) as a solid. ESI-MS: m/z 934 [M+H]⁺.

To a solution of 33-8 (7.5 g, 8.0 mmol) in dry DMF (100 mL) was addedNaOBz (11.5 g, 80.0 mmol) and 15-crown-5 (15.6 mL). The mixture wasstirred for 36 h. at 90° C. The mixture was diluted with H₂O (100 mL),and extracted with EA (3×150 mL). The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column chromatography (EA in PE from 10% to 30%)to give crude 33-9 (6.0 g, 80.0%) as a solid. ESI-MS: m/z 928 [M+H]⁺.

Compound 33-9 (4.0 g, 4.3 mmol) was co-evaporated with anhydrous toluene3 times, and treated with NH₃/MeOH (50 mL, 4N) at RT. The mixture wasstirred for 18 h. at RT. Completion of the reaction was determined byLCMS. The mixture was concentrated at low pressure, and the residue waspurified by silica gel column chromatography (EA in PE from 30% to 50%)to give product 33-10 (1.9 g, 71.7%) as a solid. ESI-MS: m/z 616 [M+H]⁺.

Compound 33-10 (300.0 mg, 0.49 mmol) was co-evaporated with anhydroustoluene 3 times, and was dissolved in MeCN (2 mL). The mixture wastreated with NMI (120.5 mg, 1.47 mmol) and the phosphorochloridatereagent (326.3 mg, 0.98 mmol) in MeCN (1 mL) at 0° C. The mixture wasstirred for 18 h at RT and monitored by LCMS. The mixture was dilutedwith 10% NaHCO₃ solution, and extracted with EA (3×30 mL). The residuewas purified by silica gel column chromatography (EA in PE from 30% to50%) to give 33-11 (210 mg, 47.5%) as a solid. ESI-MS: m/z 913.0 [M+H]⁺.

Compound 33-11 (210 mg, 0.26 mmol) was treated with 80% of AcOH (15 mL),and the mixture was stirred for 18 h at RT. Completion of the reactionwas determined by LCMS. The mixture was concentrated at low pressure,and the residue was purified by silica gel column chromatography (MeOHin DCM from 1% to 3%) to give compound 33 (71.8 mg, 48.7%) as a solid.ESI-MS: m/z 641.3 [M+H]⁺.

Example 59 Compound 75

A mixture solution of 1-5 (317 mg, 0.49 mmol), TPSCl (373 mg, 1.23mmol), DMAP (150 mg, 1.23 mmol) and TEA (124 mg, 1.23 mmol) in anhydrousMeCN was stirred at RT overnight. The mixture was treated with ammoniumsolution, and then stirred at RT for 3 h. The solvent was removed underreduced pressure, and the residue was purified by column chromatographyto give 75-1 (200 mg, 63%).

A solution of 75-1 (286 mg, 0.45 mmol) and ammonium fluoride (500 mg,13.5 mmol) in methanol (10 mL) was refluxed overnight. The solvent wasremoved under reduced pressure and the residue was purified on silicagel to give compound 75 (75 mg, 57%). ESI-MS: m/z 289.9 [M+H]⁺.

Example 60 Compound 76

Compound 76-1 (0.44 g, 34%) was prepared from 52-3 (0.88 g, 1.48 mmol)and triethylammonium bis(isobutyryloxymethyl)phosphate (3 mmol) withDIPEA (1.05 mL), BopCl (0.76 g), and 3-nitro-1,2,4-triazole (0.34 g) inTHF (10 mL). Purification was done with hexanes/EtOAc (5-100% gradient).Compound 76-2 (0.43 g, 85%) was prepared from 76-1 (0.44 g); andcompound 76 (0.19 g, 98%) was prepared from 76-2 (0.22 g) in EtOH (10mL) with 10% Pd/C (10 mg), 4 N HCl/dioxane (132 μL), and under the H₂atmosphere. The aforementioned reactions were conducted using a methoddescribed in the preparation of compound 52. MS: m/z=700 [M+1].

Example 61 Compound 77

To a stirred solution of 77-1 (2.0 g, 7.12 mmol) in pyridine (20 mL) wasadded TMSCl (3.86 g, 35.58 mmol) at 0° C. under N₂. The mixture wasslowly warmed to RT and stirred for 2 h. PivCl (1.71 g, 14.23 mmol) wasadded, and the mixture was stirred for 24 h. The solvent was evaporatedat low pressure, and the residue was dissolved in EA (50 mL). Thesolution was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure to give the crude product. The crudeproduct was dissolved in MeOH (20 mL) and NH₄F (1.4 g, 37.86 mmol) wasadded. The mixture was refluxed for 2 h. The solvent was removed, andthe residue was purified by column chromatography to give 77-2 (2.2 g,85%).

To a solution of 77-2 (8.5 g, 23.28 mmol) and 1,1-dimethoxycyclopentane(2 mL) in a mixture of DMF (15 mL) and cyclopentanone (6 mL) was addedTsOH (6.63 g, 34.93 mmol). The mixture was stirred at RT for 12 h. Thereaction was quenched with triethylamine, and concentrated at lowpressure. The residue was purified by column chromatography to give 77-3(6.5 g, 65%).

To a stirred solution of 77-3 (6.0 g, 13.92 mmol) in anhydrous MeOH (60mL) was added MeONa (2.25 g, 41.76 mmol) at RT. The mixture was stirredfor 12 h and then neutralized with HOAc. The mixture was concentrated atlow pressure, and the residue was purified by column chromatography togive 77-4 (4.4 g, 92%).

To a stirred solution of 77-4 (5.0 g, 14.40 mmol) in anhydrous pyridine(50 mL) was added TBSCl (3.24 g, 21.61 mmol) at RT under N₂, and themixture was stirred overnight. The mixture was concentrated at lowpressure, and the residue was purified by column chromatography to give77-5 (5.44 g, 82%).

To a stirred solution of 77-5 (5.0 g, 10.84 mmol) in anhydrous DCM (50mL) was added MMTrCl (5.01 g, 16.26 mmol), collidine (5 mL), and AgNO₃(2.76 g, 16.26 mmol) at RT under N₂, and the mixture was stirred for 2h. The precipitate was removed by filtration, and the filtrate wasconcentrated at low pressure. The residue was purified by columnchromatography to give 77-6 (7.1 g, 89%).

To a stirred solution of 77-6 (7.1 g, 9.68 mmol) in anhydrous THF (70mL) was added TBAF (5.05 g, 19.37 mmol) at RT under N₂, and the mixturewas stirred for 4 h. The mixture was concentrated at low pressure, andthe residue was purified by column chromatography to give 77-7 (5.1 g,87%).

To a stirred solution of 77-7 (3.2 g, 5.17 mmol) and pyridine (2.04 g,25.85 mmol) in anhydrous DCM (30 mL) was added DMP (3.28 g, 7.75 mmol)at RT under N₂. The mixture was stirred at RT for 3 h. The reaction wasquenched with sat. Na₂S₂O₃ solution, and washed with sat. NaHCO₃solution and brine. The organic phase was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The residue was purified by columnchromatography to give the aldehyde (1.8 g). To a stirred solution ofthe aldehyde (1.8 g, 2.92 mmol) in dioxane (29.2 mL) was added 37% HCHO(2.36 g, 29.17 mmol) and 1N LiOH (1.6 mL, 2.34 mmol) at RT. The mixturewas stirred at RT for 1.5 h. The solution was neutralized with HOAc. Themixture was treated with EtOH (15 mL) and NaBH₄ (1.66 g, 43.8 mmol), andstirred at RT for 2 h. The mixture was quenched with water, andconcentrated at low pressure. The residue was purified by columnchromatography to give 77-8 (2.01 g, 61%).

To a stirred solution of 77-8 (200 mg, 0.31 mmol) in anhydrous DCM (2mL) was added TBDPSCl (170 mg, 0.62 mmol) and imidazole (42 mg, 0.62mmol) at RT under N₂. The mixture was stirred at RT for 2 h. The mixturewas diluted with DCM (10 mL), and washed with brine. The organic phasewas concentrated at low pressure, and the residue was purified by columnchromatography to give 77-9 (175 mg, 64%).

To a stirred solution of 77-9 (270 mg, 0.304 mmol) in anhydrous DCM (2mL) was added BzCl (63 mg, 0.61 mmol), DMAP (74 mg, 0.61 mmol) and TEA(61 mg, 0.61 mmol) at RT under N₂. The mixture was stirred at RT untilthe starting material disappeared. The =mixture was evaporated at lowpressure, and the residue was purified by column chromatography to give77-10 (250 mg, 83.3%).

Compound 77-10 (300 mg, 0.302 mmol) in THF (5 mL) was treated with asolution of TBAF (0.61 mL, 0.61 mmol, 1M in THF) and HOAc (0.2 mL) atRT. The mixture was stirred at RT for 12 h. The mixture was concentratedat low pressure, and the residue was purified by column chromatographyto give 77-11 (170 mg, 75%).

To a stirred solution of 77-11 (400 mg, 0.531 mmol) in anhydrous DCM (4mL) was added Tf₂O (299 mg, 1.06 mmol) and pyridine (84 mg, 1.06 mmol)at RT under N₂. The mixture was stirred at RT until the startingmaterial disappeared. The mixture was concentrated at low pressure, andthe residue was purified by column chromatography to give 77-12 (401 mg,85%).

Compound 77-12 (500 mg, 0.564 mmol) was treated with TBAF in THF (1.0 M,2 mL) at RT under N₂. The mixture was diluted with water (20 mL), andextracted with DCM. The solution was washed with brine, dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by column chromatography to give 77-13 (150 mg, 40.8%) as awhite solid. ESI-MS: m/z 652.1 [M+H]⁺.

Compound 77-13 (50 mg) was dissolved in 80% HCOOH (10 mL), and themixture was heated at 45° C. for 24 h. The solvent was evaporated andco-evaporated with methanol/toluene to remove traces of acid. Theresidue was dissolved in 20% triethylamine in methanol, kept for 15 minsand then evaporated. Compound 77 (18 mg, 75%) was isolated by silica gelchromatography in a gradient of methanol in DCM from 0% to 15%. MS: m/z312.5 [M−1].

Example 62 Compound 78

Compound 78a was prepared from commercially available 3-hydroxyoxetane(5.0 g). ¹H-NMR (CDCl₃) δ 5.73 (s, 2H), 5.48-5.51 (m, 1H), 4.90 (d, 2H),4.72 (d, 2H). Compound 78b (8.0 g) was prepared from 78a. ¹H-NMR (CDCl₃)δ 5.95 (s, 2H), 5.48-5.51 (m, 1H), 4.90 (d, 2H), 4.72 (d, 2H).Benzylphosphate (silver salt) and 78b (8.0 g) were reacted to yieldpurified 78c (1.92 g). ¹H-NMR (CD₃CN): δ 7.39-7.42 (m, 5H), 5.62 (d,4H), 5.39-5.42 (m, 2H), 5.15 (d, 2H), 4.80-4.83 (m, 4H), 4.56-4.60 (m,4H). ³¹P-NMR (CD₃CN): δ −4.55 ppm. Compound 78c was deprotected to give78-1 (triethylammonium salt), which was used immediately without furtherpurification. Compound 54-6 (356 mg; 1.0 mmol) and 78-1 were reacted togive purified 78-2 (230 mg). Compound 78-2 (230 mg) was deprotected toyield purified compound 78 (12.5 mg, 0.02 mmol). The aforementionedreactions were conducted using a method described in the preparation ofcompound 54. ¹H-NMR (CDCl₃): δ 8.25 (s, 1H), 7.54 (d, 1H), 5.90 (s, 1H),5.81 (d, 1H), 5.66-5.75 (m, 4H), 5.44-5.49 (m, 2H), 4.88-4.92 (m, 5H),4.61-4.78 (m, 5H), 4.37-4.46 (m, 2H), 4.21 (s, 1H), 3.49 (s, 1H), 1.25(s, 3H). ³¹P-NMR (CDCl₃): δ −4.28 ppm.

Example 63 Compound 83

Compound 83-2 (70 mg, 58%) was prepared in the same manner from compound83-1 (90 mg; 0.1 mmol) and triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.2 mmol) with DIPEA (87μL), BopCl (44 mg), and 3-nitro-1,2,4-triazole (29 mg) in THF (2 mL) asdescribed in the preparation of compound 44. Purification was done withhexanes/EtOAc with a 20-80% gradient.

Compound 83 (25 mg, 64%) was prepared from 83-2 (70 mg) in acetonitrile(0.6 mL) and 4 N HCl/dioxane (50 μL) as described in the preparation ofcompound 55. MS: m/z=658 [M+1].

Example 64 Compound 84

Compound 84-2 (69 mg, 90%) was prepared from 84-1 (52 mg; 0.08 mmol) andtriethylammonium bis(isopropyloxycarbonyloxymethyl)phosphate (0.16 mmol)with DIPEA (74 μL), BopCl (51 mg), and 3-nitro-1,2,4-triazole (23 mg) inTHF (1 mL) as described in the preparation of compound 44. Purificationwas done with hexanes/EtOAc with a 20-100% gradient.

Compound 84 (27 mg, 62%) was prepared from 84-2 (65 mg) as described inthe preparation of compound 44. MS: m/z=626 [M+1].

Example 65 Compound 85

A mixture of 76-2 and acetic anhydride in pyridine was stirred overnightat RT, then concentrated and purified on silica gel (10 g column) withCH₂Cl₂/i-PrOH (4-10% gradient) to yield 85-1 (12 mg, 69%).

Compound 85 (10 mg, 92%) was prepared from 85-1 (12 mg) in EtOH (0.5 mL)with 10% Pd/C (1 mg), 4 N HCl/dioxane (7 μL), and under the H₂atmosphere in the same manner compound 52. MS: m/z=742 [M+1].

Example 66 Compounds 86 and 87

A freshly prepared EtONa in dry EtOH (2N, 150 mL) was added to asolution of 20-4 (13.67 g, 17.15 mmol) in EtOH (50 mL) at 0° C. Themixture was stirred at RT for 1 h, and then concentrated at lowpressure. The residue was purified by silica gel column (5% MeOH in DCM)to give 86-1 (10 g, 98%) as a yellow solid.

To a solution of PPh₃ (2.73 g, 10.4 mol) in anhydrous pyridine (60 mL)was added I₂ (2.48 g, 9.76 mmol) at RT, and the reaction mixture wasstirred RT for 30 mins. A solution of 86-1 (3.9 g, 6.51 mmol) inpyridine (10 mL) was added. The mixture was stirred at RT overnight. Thereaction was quenched with sat. Na₂S₂O₃ solution and NaHCO₃ aq., andthen extracted with EA (100 mL). The organic layer was dried overanhydrous Na₂SO₄, and evaporated at low pressure. The residue waspurified by silica gel column (2% MeOH in DCM) to give 86-2 (3.0 g, 75%)as a yellowed solid.

To a solution of 86-2 in dry THF (300 mL) was added DBU (14.0 g, 91.8mmol), and the mixture was heated to reflux for 3 h. The mixture wasconcentrated at low pressure. The residue was dissolved in EA (100 mL),and washed with brine. The organic layer was dried over anhydrousNa₂SO₄, and evaporated at low pressure. The residue was purified bysilica gel column (20% EA in PE) to give 86-3 (0.6 g, 37.5%) as a whitesolid.

To an ice-cooled solution of 86-3 (2.0 g, 3.44 mmol) in anhydrous MeCN(20 mL) was added NIS (0.975 g, 4.3 mmol) and TEA.3HF (0.82 g, 5.16mmol) at 0° C. The mixture was stirred at RT for 2 h. The reaction wasquenched with sat. Na₂SO₃ and NaHCO₃ aqueous solution, and thenconcentrated at low pressure. The residue was dissolved in EA (50 mL),washed with brine, dried over anhydrous Na₂SO₄, and evaporated at lowpressure. The residue was purified by silica gel column (20% EA in PE)to give 86-4 (1.5 g, 60%) as a white solid.

To a solution of 86-4 (1 g, 1.37 mmol) in dry pyridine (100 mL) wasadded BzCl (0.23 g, 1.65 mmol) at 0° C. The reaction was stirred for 30mins and checked by LCMS. The mixture was concentrated at low pressure,and the residue was dissolved in EA (50 mL). The solution was washedwith brine. The organic layer was dried over MgSO₄, and evaporated atlow pressure. The residue was purified by silica gel columnchromatography (10% EA in PE) to give 86-5 (0.9 g, 78%) as a whitesolid.

To a solution of 86-5 (2 g, 2.4 mmol) in dry DMF (40 mL) was added NaOBz(3.46 g, 24 mmol) and 15-crown-5 (4.5 mL). The mixture was stirred at95° C. for 72 h. The mixture was then diluted with EA (100 mL), andwashed with water and brine. The organic phase was dried over MgSO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn (15% EA in PE) to give 86-6 (1.5 g, 75%) as a white solid.

Compound 86-6 (1.35 g, 1.64 mmol) in NH₃/MeOH (150 mL) was stirred at RTfor 18 h. The mixture was concentrated at low pressure, and the residuewas purified by silica gel column (5% MeOH in DCM) to give 86-7 (0.9 g,90%) as a white solid. ESI-MS: m/z 618.3 [M+H]⁺.

To a solution of 86-7 (99 mg, 0.16 mmol) in DCM (1.0 mL), triethylamine(92.7 μL, 0.64 mmol) was added at RT. The mixture was cooled to 0 to 5°C. (ice/water bath), and freshly prepared and distilled isopropylphosphorodichloridate (36.6 μL, 0.2 mmol, prepared according to aprocedure, Reddy et al., J. Org. Chem. (2011) 76 (10):3782-3790) wasadded to the mixture. The mixture was stirred 0 to 5° C. (ice/waterbath) for 15 mins, followed by addition of N-methylimidazole (26.3 μL,0.32 mmol). The mixture was then stirred for 1 h at 0 to 5° C. TLCshowed absence of 86-7. EA (100 mL) was added, followed by water. Theorganic layer was washed H₂O, saturated aqueous NH₄Cl solution andbrine. The organic layer was separated, dried over anhydrous MgSO₄ andfiltered. The filtrate was concentrated in vacuum to give a residue,which was purified on silica gel with 0 to 10% iPrOH/DCM to give amixture of 86-a and 86-b (61.5 mg).

A mixture of 86-a and 86-b (61.5 mg, 0.085 mmol) was dissolved inanhydrous CH₃CN (0.5 mL), and 4N HCl in dioxane (64 μL) was added at 0to 5° C. (ice/water bath). The mixture was stirred at RT for 40 mins,and anhydrous EtOH (200 μL) was added. The solvents were evaporated atRT and co-evaporated with toluene 3 times. The residue was dissolved in50% CH₃CN/H₂O, was purified on a reverse-phase HPLC (C18) usingacetonitrile and water, followed by lyophilization to give compound 86(1.8 mg) and compound 87 (14.5 mg).

Compound 86: ¹H NMR (CD₃OD-d₄, 400 MHz) δ 8.0 (s, 1H), 6.69 (d, J=16.0Hz, 1H), 5.9-5.6 (br s, 1H), 4.94-4.85 (m, 1H), 4.68-4.52 (m, 3H),1.49-1.3 (m, 12H); ¹⁹F NMR (CD₃OD-d₄) δ −122.8 (s), −160.06 (s); ³¹P NMR(CD₃OD-d₄) δ −7.97 (s). ESI-LCMS: m/z=450.1 [M+H]⁺; Compound 87: ¹H NMR(CD₃OD-d₄, 400 MHz) δ 7.96 (s, 1H), 6.68 (s, 1H), 6.69 (d, J=16.8 Hz,1H), 6.28-6.1 (br s, 1H), 4.81-4.5 (m, 4H), 1.45-1.39 (m, 12H); ³¹P NMR(CD₃OD-d₄) δ −5.84 (s). ESI-LCMS: m/z=450. [M+H]⁺.

Example 67 Compounds 88 and 89

To a solution of 88-1 (150 mg, 0.24 mmol) in DCM (2.0 mL), triethylamine(141 μL, 2.0 mmol) was added at RT. The mixture was cooled to 0 to 5° C.(ice/water bath), and freshly prepared and distilled isopropylphosphorodichloridate (45 μL, 0.26 mmol, prepared according to aprocedure, Reddy et al., J. Org. Chem. (2011) 76 (10):3782-3790) wasadded. The mixture was stirred at 0 to 5° C. (ice/water bath) for 15mins, followed by N-methylimidazole (40 μL, 0.49 mmol). The mixture wasstirred for 1 h at 0 to 5° C. TLC showed the absence of startingmaterial 88-1. EA (100 mL) was added, followed by water. The organiclayer was washed with H₂O, sat. aq. NH₄Cl solution and brine. Theorganic layer was separated, dried over anhydrous MgSO₄ and filtered.The filtrate was concentrated in vacuum to give a residue, which waspurified on silica gel with 0 to 10% iPrOH/DCM to give 88-2a (16.9 mg,faster eluting isomer) and 88-2b (72.7 mg, slower eluting isomer).

Compounds 88-2a and 88-2b were deprotected using a procedure describedherein. Compound 88 (7.3 mg, single isomers from 88-2a (16.5 mg, 0.0235mmol)) and compound 89 (29.0 mg. single isomers from 88-2b (72.7 mg, 0.1mmol)) were obtained.

Compound 88: ¹H NMR (CD₃OD-d₄, 400 MHz) δ 7.94 (s, 1H), 6.32 (s, 1H),6.00-5.9 (br s, 1H), 4.9-4.487 (m, 1H), 4.83-4.77 (m, 1H), 4.65-4.50 (m,3H), 1.45-1.39 (s, 9H), 1.2 (s, 3H); ¹⁹F NMR (CD₃OD-d₄) δ −120.3 (s);³¹P NMR (CD₃OD-d₄) δ −5.19 (s); ESI-LCMS: m/z=448.05 [M+H]⁺. Compound89: ¹H NMR (CD₃OD-d₄, 400 MHz) δ 7.98 (s, 1H), 6.34 (s, 1H), 5.78-5.64(br s, 1H), 4.95-4.48 (m, 2H), 4.62-4.52 (m, 3H), 1.48-1.42 (s, 9H), 1.1(s, 3H); ¹⁹F NMR (CD₃OD-d₄) δ −121.3 (s); ³¹P NMR (CD₃OD-d₄) δ −7.38(s); ESI-LCMS: m/z=448.05 [M+H]⁺.

Example 68 Compound 90

To a stirred solution of 90-1 (532 mg, 1.84 mmol) in anhydrous CH₃CN(8.0 mL) was added N-methylimidazole (2.0 mL, 24.36 mmol) at 0 to 5° C.(ice/water bath) followed by a solution of freshly prepared anddistilled isopropyl phosphorodichloridate (0.5 mL, 2.84 mmol). Thesolution was stirred at RT for 15 h. The mixture was diluted with EA,followed by water (15 mL). The solution was washed with H₂O, 50% aqueouscitric acid solution and brine. The organic layer was separated, driedover anhydrous MgSO₄ and filtered. The filtrate was concentrated invacuum to give a residue, which was purified on silica gel with 0 to 8%MeOH/DCM to give the crude product (72 mg). The crude product wasre-purified purified on a reverse-phase HPLC (C18) using acetonitrileand water, followed by lyophilization to give compound 90 (43.6 mg). MS:m/z=395.05 [M+H]⁺, 393.0 [M−H]⁻, 787.05.0 [2M−H]⁻.

Example 69 Compound 96

Dry 51 (0.05 mmol) was dissolved in the mixture of PO(OMe)₃ (0.7 mL) andpyridine (0.3 mL). The mixture was evaporated in vacuum for 15 mins atbath temperature 42° C., and then cooled to RT. N-Methylimidazole (0.009mL, 0.11 mmol) was added followed by POCl₃ (9 ul, 0.11 mmol), and themixture was kept at RT for 20-40 mins. The reaction was controlled byLCMS and monitored by the appearance of compound 96. Isolation wasperformed by RP HPLC on Synergy 4 micron Hydro-RP column (Phenominex). Alinear gradient of methanol from 0 to 30% in 50 mM triethylammoniumacetate buffer (pH 7.5) was used for elution. The correspondingfractions were combined, concentrated and lyophilized 3 times to removeexcess of buffer to yield compound 96. MS: m/z 369.0 [M−1].

Example 70 Compounds 97 and 98

Dry 51 (0.05 mmol) was dissolved in the mixture of PO(OMe)₃ (0.7 mL) andpyridine (0.3 mL). The mixture was evaporated in vacuum for 15 mins atbath temperature 42° C., than cooled to RT. N-Methylimidazole (0.009 mL,0.11 mmol) was added followed by PSCl₃ (9 uL, 0.11 mmol), and themixture was kept at RT for 20-40 mins. The reaction was controlled byLCMS and monitored by the appearance of the nucleoside 5′-thiophosphate.After completion of the reaction, tetrabutylammonium salt ofpyrophosphate (150 mg) was added, followed by DMF (0.5 mL) to get ahomogeneous solution. After 1.5 hours at ambient temperature, thereaction was quenched with water (10 mL). The 5′-triphosphate as mixtureof diastereomers was isolated by IE chromatography on AKTA Explorerusing column HiLoad 16/10 with Q Sepharose High Performance. Separationwas done in linear gradient of NaCl from 0 to 1N in 50 mM TRIS-buffer(pH 7.5). Fractions containing thiotriphosphate were combined,concentrated and desalted by RP HPLC on Synergy 4 micron Hydro-RP column(Phenominex). Linear gradient of methanol from 0 to 30% in 50 mMtriethylammonium buffer was used for elution over 20 mins, flow 10mL/mins. Compounds 97 and 98 were collected. Analytical RP HPLC was donein 50 mM triethylammonium acetate buffer, pH 7.5 containing lineargradient of acetonitrile from 0% to 25% in 7 mins on Synergy 4 micronHydro-RP column (Phenominex). Compound 97: RT 5.50 mins. ³¹P NMR: δ+42.45 (1P, d), −6.80 (1P, d), −23.36 (1P, q). MS: m/z 544.9 [M−1].Compound 98: RT 6.01 mins. ³¹P NMR: δ +41.80 (1P, d), −6.57 (1P, d),−23.45 (1P, q). MS: m/z 544.9 [M−1].

Example 71 Compound 99

To a solution of 99a (0.31 g, 0.8 mmol) in anhydrous methanol (2 mL),was added 10% Pd/C (30 mg), and the mixture was stirred under H₂atmosphere for 1 h. After completion, the mixture was filtered, and thecatalyst cake was washed with methanol. The washing and filtrate werecombined. The solvent was removed under vacuum to give 99b as asemi-solid (252 mg), which was used without further purification. ¹H NMR(CDCl₃, 400 MHz) δ 5.57 (d, J=13.6 Hz, 4H), 4.23 (q, J=7.2 Hz, 4H), 1.30(t, J=7.2 Hz, 6H), ³¹P NMR (CDCl₃) δ −4.64 (s).

To a solution of triethylammonium bis (EOC) phosphate (0.7 mmol,prepared from 213 mg of 99b and 0.2 mL of TEA) in THF (3 mL) was added99-1 (160 mg, 0.45 mmol) followed by diisopropylethylamine (0.33 mL, 1.8mmol), BOP-Cl (229 mg, 0.9 mmol), and 3-nitro-1,2,4-triazole (103 mg,0.9 mmol). The mixture was stirred at RT for 90 mins. The mixture wasdiluted with EtOAc, and washed with water and brine. The organic layerwas separated, dried over anhydrous Na₂SO₄ and filtered. The filtratewas concentrated in vacuum to a white solid, which was purified onsilica gel column (CH₃OH:DCM; 9.5:0.5) to give 99-2 (189 mg, 66%).

To a solution of 99-2 (180 mg, 0.28 mmol) in 80% HCOOH (7 mL), washeated for 6 h at 45° C. The solvents were evaporated, and thenco-evaporated with toluene 3 times. The residue was purified on silicagel column using 0 to 10% MeOH in DCM to obtain compound 99 (97.3 mg) asa white foam after lypholization. MS: m/z=575.1 [M+H]⁺.

Example 72 Compound 100

Compound 100a was prepared from commercially available2-(2-methoxyethoxy)-ethanol (11.56 mL). Compound 100a (13.5 g) wasobtained as a clear colorless oil. ¹H-NMR (CDCl₃) δ 5.73 (s, 2H),4.38-4.40 (m, 2H), 3.74-3.77 (m, 2H), 3.64-3.67 (m, 2H), 3.54-3.57 (m,2H), 3.39 (s, 3H). Compound 100b (9.6 g) was prepared from 100a, and wasobtained as a clear, slightly colored oil. ¹H-NMR (CDCl₃) δ 5.96 (s,2H), 4.38-4.40 (m, 2H), 3.74-3.77 (m, 2H), 3.64-3.67 (m, 2H), 3.54-3.57(m, 2H), 3.39 (s, 3H). Benzylphosphate (silver salt) and 100b (2.4 g)were reacted and yielded purified 100c (1.02 g). ¹H-NMR (CD₃CN): δ7.39-7.42 (m, 5H), 5.60 (d, 4H), 5.11 (d, 2H), 4.27-4.29 (m, 4H),3.65-3.67 (m, 4H), 3.56 (t, 4H), 3.46 (t, 4H), 3.30 (s, 6H). ³¹P-NMR(CD₃CN): δ −4.55 ppm. Compound 100c (620 mg; 1.15 mmol) was deprotectedto give 100-1 (triethylammonium salt), which was used immediatelywithout further purification. Compound 54-6 (356 mg; 1.0 mmol) and 100-1were reacted to give purified 100-2 (250 mg). Compound 100-2 (250 mg)was deprotected to yield purified compound 100 (110 mg, 0.14 mmol). Theaforementioned reactions were conducted using a method described in thepreparation of compound 54. ¹H-NMR (CDCl₃): δ 8.62 (s, 1H), 7.54 (d,1H), 5.96 (s, 1H), 5.64-5.79 (m, 5H), 4.76 (dd, 2H), 4.37-4.46 (m, 6H),4.25 (d, 2H), 3.86 (s, 1H), 3.75 (t, 4H), 3.70 (t, 4H), 3.58 (t, 4H),3.38 (s, 6H), 1.65 (s, 6H), 1.25 (s, 3H). ³¹P-NMR (CDCl₃): δ −3.90 ppm.

Example 73 Compound 104

Compound 44 (0.010 g, 0.016 mmol) was added to normal saline solution (3mL, pH 7.3), and stored in a heat block at 37° C. for 6 days. Themixture was purified by preparative HPLC using a Synergi 4u Hydro-RPcolumn (Phenomenex, 00G-4375-U0-AX), with H₂O (0.1% formic acid) and ACN(0.1% formic acid) solvents (0-65% gradient in 20 minutes). The compoundeluted at 13.0 mins. Pure fractions were pooled and lyophilized to yieldcompound 104 (0.005 g, 63%). MS: m/z=487 [M+1].

Example 74 Compound 102

A mixture of 102-1 (45 mg, 0.06 mmol) and butylamine (0.4 mL) was keptovernight at RT and then evaporated. The crude residue was purified onsilica gel (10 g column) with CH₂Cl₂/MeOH (4-12% gradient) to yield102-2 as a colorless glass (20 mg, 56%).

To a solution of 102-2 (20 mg, 0.03 mmol) in ACN (0.5 mL) was added 4NHCl in dioxane (35 μL). The mixture was stirred at RT for 4 h and thenquenched with MeOH. The residue was treated with ACN to yield compound102 as an off-white solid (9 mg, 80%). MS m/z=328 [M+1].

Example 75 Compound 105

To a solution of 105-1 (50 g, 203 mmol) in anhydrous pyridine (200 mL)was added TBDPS-Cl (83.7 g, 304 mmol). The reaction was allowed toproceed overnight at RT. The solution was concentrated under lowpressure to give a residue, which was partitioned between ethyl acetateand water. The organic layer was separated, washed with brine, driedover magnesium sulfate and concentrated under reduced pressure to give5′-OTBDPS ether as a white foam (94 g).

To a solution of the 5′-OTBDPS ether (94.0 g, 194.2 mmol) in anhydrousDCM (300 mL) were added silver nitrate (66.03 g, 388.4 mmol) andcollidine (235 mL, 1.94 mol). The mixture was stirred at RT. After 15mins, the mixture was cooled to 0° C., and monomethoxytrityl chloride(239.3 g, 776.8 mmol) was added as a single portion. After being stirredovernight at RT., the mixture was filtered through Celite and thefiltrate was diluted with TBME. The solution was washed successivelywith 1M citric acid, diluted brine and 5% sodium bicarbonate. Theorganic solution was dried over sodium sulfate and concentrated undervacuum to give the fully protected intermediate as a yellow foam.

This fully protected intermediate was dissolved in toluene (100 mL) andthe solution was concentrated under reduced pressure. The residue wasdissolved in anhydrous THF (250 mL) and treated with TBAF (60 g, 233mmol). The mixture was stirred for 2 h at RT., and the solvent wasremoved under reduced pressure. The residue was taken into ethyl acetateand the solution was washed first with saturated sodium bicarbonate andthen with brine. After being dried over magnesium sulfate, the solventwas removed in vacuum and the residue was purified by columnchromatography (50% EA in PE) to give 105-2 (91 g, 86.4%) as a whitefoam.

To a solution of 105-2 (13.5 g, 26 mmol) in DCM (100 mL) was addedpyridine (6.17 mL, 78 mmol). The solution was cooled to 0° C., andDess-Martin periodinane (33.8 g, 78 mmol) was added as a single portion.The reaction mixture was stirred for 4 h at RT., and quenched by theaddition of Na₂S₂O₃ solution (4%) and sodium bicarbonate aqueoussolution (4%) (the solution was adjusted to pH 6, −150 mL). The mixturewas stirred for 15 mins. The organic layer was separated, washed withdiluted brine and concentrated under reduced pressure. The residue wasdissolved in dioxane (100 mL) and the solution was treated with 37%aqueous formaldehyde (21.2 g, 10 eq.) and 2N aqueous sodium hydroxide(10 eq.). The reaction mixture was stirred at RT., overnight. Afterstirring for 0.5 h at RT., the excess of aqueous sodium hydroxide wasremoved with saturated NH₄Cl (˜150 mL). The mixture was concentratedunder reduced pressure, and the residue was partitioned between ethylacetate and 5% sodium bicarbonate. The organic phase was separated,washed with brine, dried over magnesium sulfate and concentrated. Theresidue was purified by column chromatography (2% MeOH in DCM) to give105-3 (9.2 g, 83.6%) as a white foam.

Compound 105-3 (23 g, 42.0 mmol) was co-evaporated with toluene twice.The residue was dissolved in anhydrous DCM (250 mL) and pyridine (20mL). The solution was cooled to 0° C., and triflic anhydride (24.9 g,88.1 mmol) was added dropwise over 10 mins. At this temperature, thereaction was stirred for 40 mins. The reaction was monitored by TLC (PE:EA=2:1 and DCM: MeOH=15:1). After completion, the reaction mixture wasquenched with water (50 mL) at 0° C. The mixture was stirred for 30mins, and extracted with EA. The organic phase was dried over Na₂SO₄ andfiltered through a silica gel pad. The filtrate was concentrated underreduced pressure, and the residue was purified by column chromatography(50% EA in PE) to give 105-4 (30.0 g, 88.3%) as a brown foam.

To a stirred solution of 105-4 (4.4 g, 5.42 mmol) in anhydrous DMF (50mL) was added NaH (260 mg, 6.5 mmol) at 0° C. under nitrogen atmosphere.The solution was stirred at RT., for 1.5 h. The solution was used forthe next step without any further workup.

To the stirred solution was added NaN₃ (1.5 g, 21.68 mmol) at 0° C.under nitrogen atmosphere, and the resulting solution was stirred at RT.for 1.5 h. The reaction was quenched with water, extracted with EA,washed with brine, and dried over MgSO₄. The concentrated organic phasewas used for the next step without further purification.

To a solution of 105-6 (3.0 g, 5.4 mmol) in anhydrous 1,4-dioxane (18mL) was added NaOH (5.4 mL, 2M in water) at RT. The reaction mixture wasstirred at RT. for 3 h. The reaction was diluted with EA, washed withbrine, and dried over MgSO₄. The concentrated organic phase was purifiedon a silica gel column (30% EA in PE) to give 105-7 (2.9 g, 93%) as awhite foam.

Compound 105-7 (520 mg, 0.90 mmol) was dissolved in 80% of HCOOH (20 mL)at RT. The mixture was stirred for 3 h, and monitored by TLC. Thesolvent was removed and the residue was treated with MeOH and toluenefor 3 times. NH₃/MeOH was added, and the reaction mixture was stirred atRT., for 5 mins. The solvent was concentrated to dryness and the residuewas purified by column chromatography to give compound 105 (120 mg,44.4%) as a white solid. ESI-LCMS: m/z 302.0 [M+H]⁺, 324.0[M+Na]⁺.

Example 76 Compound 106

To a stirred solution of 105-7 (1.1 g, 2.88 mmol) in anhydrous DCM (10mL) was added MMTrCl (1.77 g, 5.76 mmol), AgNO₃ (1.47 g, 8.64 mmol) andcollidine (1.05 g, 8.64 mmol) at 25° C. under a N₂ atmosphere. Thereaction was refluxed for 12 h. MeOH (20 mL) was added and the solventwas removed to dryness. The residue was purified on a silica gel column(20% EA in PE) to give 106-1 (1.6 g, 85.1%) as a white foam.

To a stirred solution of 106-1 (800 mg, 0.947 mmol) in anhydrous MeCN(10 mL) were added TPSCl (570 mg, 1.89 mmol), DMAP (230 mg, 1.89 mmol)and TEA (190 mg, 1.89 mmol) at RT. The mixture was stirred for 12 h.NH₄OH (25 mL) was added and the mixture was stirred for 2 h. The solventwas removed, and the residue was purified on a silica gel column as ayellow foam. Further purification by prep-TLC gave 106-2 (700 mg, 87.1%)as a white solid.

Compound 106-2 (300 mg, 0.355 mmol) was dissolved in 80% of HCOOH (5 mL)at RT. The mixture was stirred for 3 h, and monitored by TLC. Thesolvent was then removed and the residue was treated with MeOH andtoluene (3 times). NH₃/MeOH was added and the mixture was stirred at RT,for 5 mins. The solvent was removed and the residue was purified bycolumn chromatography to give compound 106 (124 mg, 82.6%) as a whitesolid. ESI-LCMS: m/z 301.0 [M+H]⁺, 601.0 [2M+H]⁺.

Example 77 Compound 108

To a stirred suspension of 108-1 (20 g, 77.5 mmol), PPh₃ (30 g, 114.5mmol), imidazole (10 g, 147 mmol) and pyridine (90 mL) in anhydrous THF(300 mL) was added a solution of I₂ (25 g, 98.4 mmol) in THF (100 mL)dropwise at 0° C. The mixture was warmed to room temperature (RT) andstirred at RT for 10 h. The reaction was quenched by MeOH (100 mL). Thesolvent was removed, and the residue was re-dissolved in a mixture ethylacetate (EA) and THF (2 L, 10:1). The organic phase was washed withsaturated Na₂S₂O₃ aq., and the aqueous phase was extracted with amixture of EA and THF (2 L, 10:1). The organic layer was combined andconcentrated to give a residue, which was purified on a silica gelcolumn (0-10% MeOH in DCM) to give 108-2 (22.5 g, 78.9%) as a whitesolid. ¹H NMR: (DMSO-d₆, 400 MHz) δ 11.42 (s, 1H), 7.59 (d, J=8.4 Hz,1H), 5.82 (s, 1H), 5.63 (d, J=8.0 Hz, 1H), 5.50 (s, 1H), 5.23 (s, 1H),3.77-3.79 (m, 1H), 3.40-3.62 (m, 3H), 0.97 (s, 3H).

To a stirred solution of 108-2 (24.3 g, 66.03 mmol) in anhydrous MeOH(240 mL) was added NaOMe (10.69 g, 198.09 mmol) at RT under N₂. Themixture was refluxed for 3 h. The solvent was removed, and the residuewas re-dissolved in anhydrous pyridine (200 mL). To the mixture wasadded Ac₂O (84.9 g, 833.3 mmol) at 0° C. The mixture was warmed to 60°C. and stirred for 10 h. The solvent was removed, and the residue wasdiluted with DCM, washed with saturated NaHCO₃ and brine. The organiclayer was concentrated and purified on a silica gel column (10-50% EA inPE) to give 108-3 (15 g, 70.1%) as a white solid. ¹H NMR: (CDCl₃, 400MHz) δ 8.82 (s, 1H), 7.23 (d, J=2.0 Hz, 1H), 6.54 (s, 1H), 5.85 (s, 1H),5.77 (dd, J=8.0, 2.0 Hz, 1H), 4.69 (d, J=2.4 Hz, 1H), 4.58 (d, J=2.8 Hz,1H), 2.07 (d, J=5.2 Hz, 6H), 1.45 (s, 3H).

To an ice cooled solution of 108-3 (15 g, 46.29 mmol) in anhydrous DCM(300 mL) was added AgF (29.39 g, 231.4 mmol). I₂ (23.51 g, 92.58 mmol)in anhydrous DCM (1.0 L) was added dropwise to the solution. Thereaction mixture was stirred at RT for 5 h. The reaction was quenchedwith saturated Na₂S₂O₃ and NaHCO₃, and extracted with DCM. The organiclayer was separated, dried and evaporated to dryness. The residue waspurified on a silica gel column (10-30% EA in PE) to give 108-4 (9.5 g,43.6%) as a white solid. ¹H NMR: (Methanol-d₄, 400 MHz) δ 7.52 (d, J=8.0Hz, 1H), 6.21 (s, 1H), 5.80 (d, J=17.2 Hz, 1H), 5.73 (d, J=8.0 Hz, 1H),3.58 (s, 1H), 3.54 (d, J=6.8 Hz, 1H), 2.17 (s, 3H), 2.09 (s, 3H), 1.58(s, 3H).

To a solution of 108-4 (7.0 g, 14.89 mmol) in anhydrous DMF (400 mL)were added NaOBz (21.44 g, 148.9 mmol) and 15-crown-5 (32.75 g, 148.9mmol). The reaction mixture was stirred at 130° C. for 6 h. The solventwas removed, diluted with EA and washed with water and brine. Theorganic layer was evaporated and purified on a silica gel column (10-30%EA in PE) to give 108-5 (2.8 g, 40.5%). ESI-MS: m/z 444.9 [M-F+H].

A mixture of 108-5 (4.0 g; 8.6 mmol) and liquid ammonia was keptovernight at RT in a high-pressure stainless-steel vessel. Ammonia wasthen evaporated, and the residue purified on silica (50 g column) with aCH₂Cl₂/MeOH solvent mixture (4-12% gradient) to yield compound 108 as acolorless foam (2.0 g; 84% yield). ESI-MS: m/z 275.1 [M−H]⁻.

Example 78 Compounds 109 and 110

Dry compound 108 (14 mg, 0.05 mmol) was dissolved in the mixture ofPO(OMe)₃ (0.750 mL) and pyridine (0.5 mL). The mixture was evaporated invacuum for 15 mins at bath temperature 42° C., and then cooled down toRT. N-Methylimidazole (0.009 mL, 0.11 mmol) was added followed by POCl₃(0.009 mL, 0.1 mmol). The mixture was kept at RT for 45 mins.Tributylamine (0.065 mL, 0.3 mmol) and N-tetrabutyl ammonium salt ofpyrophosphate (100 mg) was added. Dry DMF (about 1 mL) was added to geta homogeneous solution. In 1 h, the reaction was quenched with 2Mammonium acetate buffer (1 mL, pH=7.5), diluted water (10 mL) and loadedon a column HiLoad 16/10 with Q Sepharose High Performance. Theseparation was done in linear gradient of NaCl from 0 to 1N in 50 mMTRIS-buffer (pH7.5). The fractions eluted at 60% buffer B containedCompound 109 and at 80% buffer B contained Compound 110. Thecorresponding fractions were concentrated, and the residue purified byRP HPLC on Synergy 4 micron Hydro-RP column (Phenominex). A lineargradient of methanol from 0 to 30% in 50 mM triethylammonium acetatebuffer (pH 7.5) was used for elution. The corresponding fractions werecombined, concentrated and lyophilized 3 times to remove excess ofbuffer. Compound 109: P³¹-NMR (D₂0): −3.76 (s); MS: 378.2 [M−1].Compound 110: P³¹-NMR (D₂O): −9.28 (d, 1H, Pα), −12.31 (d, 1H, Pγ),−22.95 (t, 1H, Pβ); MS 515.0 [M−1].

Example 79 Compound 112

Compound 112 (36 mg, 63%) was synthesized as described for compound 2using a neopentyl ester phosphorochloridate reagent. MS: 572.6 [M−1].

Example 80 Compounds 116 and 117

Dry compound 108 (14 mg, 0.05 mmol) was dissolved in the mixture ofPO(OMe)₃ (0.750 mL) and pyridine (0.5 mL). The mixture was evaporated invacuum for 15 mins at bath temperature 42° C., and then cooled down toRT. N-Methylimidazole (0.009 mL, 0.11 mmol) was added followed by PSCl₃(0.01 mL, 0.1 mmol). The mixture was kept at RT for 1 h. Tributylamine(0.065 mL, 0.3 mmol) and N-tetrabutyl ammonium salt of pyrophosphate(200 mg) was added. Dry DMF (about 1 mL) was added to get a homogeneoussolution. In 2 h, the reaction was quenched with 2M ammonium acetatebuffer (1 mL, pH=7.5), diluted with water (10 mL) and loaded on a columnHiLoad 16/10 with Q Sepharose High Performance. Separation was done inlinear gradient of NaCl from 0 to 1N in 50 mM TRIS-buffer (pH7.5). Thefractions eluted at 80% buffer B contained compounds 116 and 117. Thecorresponding fractions were concentrated, and the residue purified byRP HPLC on Synergy 4 micron Hydro-RP column (Phenominex). A lineargradient of methanol from 0 to 20% in 50 mM triethylammonium acetatebuffer (pH 7.5) was used for elution. Two peaks were collected. Thecorresponding fractions were combined, concentrated and lyophilized 3times to remove excess of buffer. Peak 1 (more polar): ³¹P-NMR (D₂O):+42.68 (d, 1H, Pα), −9.05 (d, 1H, Pγ), −22.95 (t, 1H, Pβ); MS 530.9.0[M−1]. Peak 2 (less polar): ³¹P-NMR (D₂O): +42.78 (d, 1H, Pα), −10.12(bs, 1H, Pγ), −23.94 (t, 1H, Pβ); and MS 530.9.0 [M−1].

Example 81 Compounds 118 and 121

The diastereomers of compound 5 were separated by RP-HPLC. A gradient of10-43% ACN in H₂O over 26 mins on a Synergi Hydro RP 30×250 m 4uparticle column (Phenomenex PN 00G-4375-U0-AX) eluted compound 121 (29.5mins) and compound 118 (30.1 mins). Pure fractions were lyophilized toproduce a white powder. Compound 121: ³¹P-NMR (DMSO-d6) 3.448 ppm; MS:m/z: 544 M−1; Compound 118: ³¹P-NMR (DMSO-d6) 3.538 ppm; MS: m/z: 544M−1.

Example 82 Compounds 120 and 119

The diastereomers of compound 8 were separated by RP-HPLC. A gradient of25-52% ACN in H₂O over 26 minutes on a Synergi Hydro RP 30×250 m 4uparticle column (Phenomenex PN 00G-4375-U0-AX) eluted compound 119 (24.8mins) and compound 120 (25.3 mins). Pure fractions were lyophilized toproduce a white powder. Compound 119: ³¹P-NMR (DMSO-d6) 3.492 ppm; MS:m/z: 584 M−1. Compound 120: ³¹P-NMR (DMSO-d6) 3.528 ppm; MS: m/z: 584M−1.

Example 83 Compound 122, Bis-lithium Salt

Compound 122-1 was synthesized using a procedure similar for preparingcompound 2 using alanine benzyl ester hydrochloride. LCMS: m/z 592[M−1]⁻.

To a solution of 122-1 (1.1 g, 1.85 mmol) in dioxane (15 mL) and water(3 mL) was added aqueous triethylammonium acetate (2M, 2 mL, 4 mmol)followed by Pd—C (10%, 100 mg). The mixture was hydrogenated (balloon)for 2 h, and monitored by HPLC. The catalyst was filtered off, and thefiltrate was concentrated to dryness. The residue was suspended in 3%solution of lithium perchlorate in acetone (25 mL). The solid wasisolated by filtration, rinsed with acetone and dried under vacuum togive compound 122 (bis-lithium salt) (731 mg, 90%). LCMS: m/z 426[M−1]⁻.

Example 84 Compound 151

Compound 108 (40 mg, 0.14 mmol) and triethylammoniumbis(pivaloyloxymethyl)phosphate (0.21 mmol, prepared from 80 mg ofbis(pivaloyloxymethyl)phosphate and 30 μL of Et₃N) were renderedanhydrous by coevaporating with pyridine, followed by toluene. Theevaporated residue was dissolved in anhydrous THF (2 mL) and cooled inan ice-bath. Diisopropylethyl amine (73 μL, 3 eq.), BopCl (71 mg, 2eq.), and 3-nitro-1,2,4-triazole (32 mg, 2 eq.) were added. The mixturewas stirred at 0° C. for 90 mins. The mixture was then diluted withEtOAc, washed with sat. aq. NaHCO₃ and brine, and dried (Na₂SO₄).Purification on silica gel column with CH₂Cl₂/i-PrOH (4-10% gradient)followed by RP-HPLC purification (A: water, B: MeCN) yielded compound151 (13 mg, 16%). MS: m/z=1167 (2M−1).

Example 85 Compound 159

To a solution of triethylammoniumbis(isopropyloxycarbonyloxyethyl-1)phosphate (0.28 mmol, prepared from100 mg of bis(isopropyloxycarbonyloxyethyl-1)phosphate and 40 μL ofEt₃N) in THF was added 159-1 (60 mg, 0.18 mmol). The mixture wasevaporated and rendered anhydrous by coevaporating with pyridine followby toluene. The evaporated residue was dissolved in anhydrous THF (2.5mL) and cooled in an ice-bath. Diisopropylethyl amine (94 μL, 3 eq.) wasadded, followed by BOP-Cl (92 mg, 2 eq.) and 3-nitro-1,2,4-triazole (41mg, 2 eq.). The mixture was stirred at 0° C. for 90 mins., diluted withEtOAc and washed with sat. aq. NaHCO₃ and brine, and dried (Na₂SO₄). Theresidue was purified on a silica gel column with CH₂Cl₂/i-PrOH (3-10%gradient) to yield 159-2 (19 mg, 17%).

A solution of 159-2 (19 mg, 0.03 mmol) in 80% aq. HCOOH was stirred atRT for 90 mins., and then concentrated. The residue was coevaporatedwith toluene and then with MeOH containing small amount of Et₃N (1drop). Purification on a silica gel column with CH₂Cl₂/MeOH (4-10%gradient) yielded compound 159 (5 mg, 26%). MS: m/z=629 [M−1].

Example 86 Compound 160

A mixture of benzyloxycarbonyl-L-valine (55 mg, 0.22 mmol) in THF (1 mL)and CDI (36 mg, 0.22 mmol) was stirred at RT for 1.5 h and then at 40°C. for 20 mins. The solution was added to a mixture of compound 44 (122mg, 0.2 mmol) and DMAP (3 mg, 0.03 mmol) in DMF (1.5 mL) and TEA (0.75mL) at 80° C. The mixture was stirred at 80° C. for 1 h. After cooling,the mixture was concentrated, and the residue partitioned betweentert-butyl methyl ether and water. The organic layer was washed with 0.1N citric acid, sat. aq. NaHCO₃ and brine, and dried (Na₂SO₄). Theresidue was purified on a silica gel column with CH₂Cl₂/i-PrOH (4-10%gradient) to yield 160-1 (83 mg, 50%) as a colorless foam.

To a solution of 160-1 (83 mg, 0.1 mmol) in EtOH were added HCl (4 N indioxane; 50 μL, 2 eq.) and 10% Pd/C (5 mg). The mixture was stirredunder H₂ atmosphere (normal pressure) for 1 h. The catalyst was removedby filtration through a Celite pad, and the filtrate evaporated to yieldcompound 160 (50 mg) as a white solid. MS: m/z=702 [M+1].

Example 87 Compound 113

Compound 5-2 (32 mg, 0.1 mmol) was dissolved in dry THF (3 mL) and 2Msolution of isopropylmagnesium bromide in THF (0.1 mL) was added at 0°C. The reaction was left for 1 h at RT, andphenyl(isopropyl-L-alaninyl)thiophosphorochloridate was added (0.3mmol). The mixture was left overnight at RT. LSMS analysis showed about20% of unreacted starting material. The same amount of Grignard reagentand thiophosphorochloridate were added, and the mixture was heated at37° C. for 4 h. The reaction was quenched with NH₄Cl. The product wasextracted with EA, washed with brine, dried over Na₂SO₄, and evaporated.The resulting oil was dissolved in 80% formic acid (4 mL) and in 1 hevaporated. Compound 113 was purified by RP HPLC in gradient of methanolin water from 30% to 95% on Synergy 4u Hydro-RP column (Phenominex)yielding a colorless solid. Compound 113 (7 mg, yield 12.5%). MS 560.0(M−H).

Example 88 Compound 125

Compound 125-1 (109 mg) was dissolved in 80% HCOOH (15 mL) and kept for3 h at RT, then evaporated. The residue was treated with NH₃/MeOH for 1h at RT to remove formyl-containing side-products. After evaporationcompound 125 was purified by crystallization using methanol to yieldcompound 125 (52 mg, 86%). MS: 339.6 [M−1], 679.7 (2M−1).

Example 89

Compound 148-1 (15.0 g, 25.55 mmol) was treated with 90% HOAc (150 mL)at RT. The mixture was stirred at 110° C. for 12 h, and thenconcentrated at a low pressure. The residue was dissolved in DCM, andthe solution was washed with brine. The organic phase was dried overanhydrous Na₂SO₄, and then concentrated at a low pressure. The residuewas purified by column chromatography (5% MeOH in DCM) to give 148-2(11.0 g, 88.9%) as a white solid.

Compound 148-2 (12.0 g, 24.79 mmol) was treated with NH₃ in MeOH (200mL, 7 M) at RT. The solution was stirred at RT for 12 h, and thenconcentrated at a low pressure. The residue was purified by columnchromatography (10% MeOH in DCM) to give 148-3 (6.5 g, 95.0%) as a whitesolid.

To a stirred suspension of 148-3 (4.3 g, 15.58 mmol), PPh₃ (8.16 g,31.15 mmol), imidazole (2.11 g, 31.15 mmol) and pyridine (15 mL) inanhydrous THF (45 mL) was added a solution of I₂ (7.91 g, 31.15 mmol) inTHF (100 mL) dropwise at 0° C. The mixture was slowly warmed to RT andstirred overnight. The mixture was quenched with MeOH (100 mL). Thesolvent was removed at a low pressure, and the residue was re-dissolvedin a mixture of EA and THF (0.2 L, 10:1). The organic phase was washedwith sat. Na₂S₂O₃ aq. (2×). The aqueous phase was extracted with amixture of EA and THF (0.2 L, 10:1, 2×). The concentrated organic phasewas dried over anhydrous Na₂SO₄. The residue was purified on a silicagel column (0-10% MeOH in DCM) to afford 148-4 (5.1 g, 85.0%) as a whitesolid.

Compound 148-4 (800 mg, 2.07 mmol) was dissolved in a mixture of DBU (4mL) and THF (4 mL) at RT under N₂. The solution was stirred at RT for 1h. The mixture was neutralized with HOAc, and extracted with a mixtureof EA and THF (10:1, 40 mL). The organic phase was washed with brine,and dried over anhydrous Na₂SO₄. The concentrated organic phase waspurified by column chromatography (0-10% MeOH in DCM) to give 148-5 (240mg, 44.9%) as a white solid.

To an ice-cooled solution of 148-5 (1.20 g, 4.65 mmol) in anhydrous MeCN(12 mL) was added NIS (1.57 g, 6.97 mmol) and TEA.3HF (1.12 g, 6.97mmol) under N₂. The mixture was stirred at RT for 5 h. The reaction wasquenched with sat. NaHCO₃ solution, and extracted with EA (3×100 mL).The organic phase was dried over anhydrous Na₂SO₄, and evaporated todryness at low pressure. The residue was purified on a silica gel column(0-5% MeOH in DCM) to give 148-6 (0.91 g, 48.6%) as a white solid.

To a stirred solution of 148-6 (1.2 g, 2.97 mmol) in anhydrous DCM (12mL) was added BzCl (0.83 g, 5.94 mmol), TEA (0.6 g, 5.94 mmol) and DMAP(0.72 g, 5.94 mmol) successively at RT. The mixture was stirred at RTfor 12 h. The reaction was quenched with water, and extracted with EA(3×60 mL). The organic phase was concentrated at low pressure. Theresidue was purified by column chromatography (0-5% MeOH in DCM) to give148-7 (1.2 g, 66.2%) as a white solid.

Tetra-butyl ammonium hydroxide (25.78 mL, 51.78 mmol) was neutralizedwith TFA (4.3 mL) to pH=4, and the solution was added to a solution of148-7 (1.09 g, 2.14 mmol) in DCM (30 mL). m-CPBA (1.85 g, 10.74 mmol)was added portionwise under vigorous stirring, and the mixture wasstirred for 12 h. The mixture was diluted with EA (100 mL), and washedwith sat. sodium bicarbonate. The organic phase was concentrated at lowpressure. The residue was purified by column chromatography (50% EA inPE) to give 148-8 (350 mg, 41.1%) as a white solid.

Compound 148-8 (280 mg, 0.704 mmol) was treated with NH₃ in MeOH (10 mL,7 M) at RT. The mixture was stirred at RT for 2 h. The mixture wasconcentrated at a low pressure. The residue was purified by columnchromatography (0-10% MeOH in DCM) to give compound 148 (110 mg, 53.1%)as a white solid. ESI-LCMS: m/z 295.1 [M+H]⁺.

Example 90 Compound 150

To an ice-cooled solution of 150-1 (10 g, 42 mmol) in anhydrous MeCN(200 mL) was added TEA.3HF (10 g, 62.5 mmol) and NIS (28 g, 126 mmol).The mixture was stirred at RT for 1.5 h, and monitored by LCMS. Afterthe reaction was completed, the mixture was concentrated at a lowpressure. The residue was purified by silica gel column chromatography(15% MeCN in DCM) to give 150-2 (12 g, 74%) as a yellow solid.

To a solution of 150-2 (22 g, 57 mmol) in anhydrous DCM (200 mL) wasadded DMAP (21 g, 171 mmol) and BzCl (17.6 g, 125 mol). The mixture wasstirred for 5 h at RT, and monitored by LCMS. The solution was washedwith sat. NaHCO₃ solution and brine, and extracted with EA. The organicphase was dried over anhydrous Na₂SO₄ and filtered. The filtrate wasconcentrated at low pressure. The residue was purified by silica gelcolumn chromatography (20% EA in PE) to give 150-3 (30 g, 88%) as awhite foam.

To a solution of 150-3 (6.5 g, 11 mmol) in anhydrous DMF (270 mL) wasadded NaOBz (15.8 g, 110 mmol) and 15-crown-5 (29 g, 132 mmol). Themixture was stirred at 95° C. for 48 h. The precipitate was removed byfiltration, and the organic solvent was removed at low pressure. Theresidue was dissolved in EA (200 mL), and the solution was washed withsat. NaHCO₃ solution, and brine. The organic layer was dried overanhydrous Na₂SO₄ and filtered. The filtrate was concentrated at lowpressure. The residue was purified by silica gel column chromatography(20% EA in PE) to give 150-4 (3 g crude, 46.1%) as an oil.

Compound 150-4 (3 g, crude) was treated with NH₃ in MeOH (120 mL, 7 M).The mixture was stirred for 3 h and monitored by TLC. The solution wasconcentrated at low pressure. The residue was purified by silica gelcolumn chromatography (10% isopropanol in DCM) to give 150-5 (1.0 g,67%) as a white solid. ¹H-NMR (CD₃OD, 400 MHz) δ=1.19 (s, 3H), 3.76-3.82(m, 2H), 4.02 (d, J=19.8 Hz, 1H), 5.70 (d, J=8.07 Hz, 1H), 6.27 (s, 1H),7.89 (d, J=8.07 Hz, 1H).

Compound 150-5 (100 mg, 0.36 mmol) was co-evaporated with toluene 3times. To a stirred solution of 150-5 (100 mg, 0.36 mmol) in a mixtureof MeCN (1.0 mL) and NMI (295 mg, 3.6 mmol) was added a solution of150-C (255.6 mg, 0.72 mmol, preparation described below) in MeCN (0.5mL) at 0° C. The mixture was stirred at RT overnight. The reaction wasquenched with water, and diluted with EA (20 mL). The organic layer waswashed with water and brine. The organic layer was dried over anhydrousNa₂SO₄. The organic phase was concentrated at low pressure. The residuewas purified on a silica gel column (5% i-PrOH in DCM) to give the crudeproduct. The product was purified by prep-HPLC (0.1% HCOOH in water andMeCN) to give compound 150 (46.7 mg, 23.3%) as a white solid. ESI-LCMS:m/z 618 [M+Na]⁺.

To a stirred solution of 150-A (2.0 g, 13.16 mmol) and naphthalen-1-ol(1.89 g, 13.16 mmol) in anhydrous DCM (100 mL) was added a solution ofTEA (1.33 g, 13.16 mmol) in DCM (20 mL) dropwise at −78° C. Afteraddition, the mixture was gradually warmed to RT, and stirred for 2 h.The solution was cooled to −78° C., and (S)-isopropyl 2-aminopropanoatehydrochloride (2.20 g, 13.16 mmol) in DCM (20 mL) was added, followed byTEA (2.66 g, 26.29 mmol) in DCM (20 mL) dropwise. The mixture wasgradually warmed to RT, and stirred for 2 h. The organic solvent wasremoved at low pressure. The residue was dissolved in methyl-butylether. The precipitate was filtered, and the filtrate was concentratedat low pressure. The residue was purified on a silica gel column(anhydrous DCM) to give 150-C (1.0 g, 24.8%) as a colorless oil.

Example 91 Compounds 152 and 153

To a solution of 150-5 (300 mg, 1.08 mmol) and NMI (892 mg, 10 mmol) inanhydrous MeCN (4 mL) was added a solution of 152-C (736 mg, 2.17 mmol,preparation described below) in anhydrous MeCN (1 mL) dropwise at 0° C.The mixture was stirred at RT overnight. The reaction was quenched withwater, and diluted with EA (30 mL). The organic layer was washed withwater and brine. The organic phase was dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The residue was purified by a silica gelcolumn (iPrOH in DCM from 1% to 5%) to give crude compound 152 (276 mg,crude). Crude compound 152 (96 mg) was purified by prep-HPLC (0.1% HCOOHin water and MeCN) to give pure compound 152 (46 mg, 47.9%) as a whitesolid. ESI-LCMS: m/z 560 [M-F]⁺.

To a solution of compound 152 (180 mg, 0.31 mmol) in anhydrous pyridine(6 mL) was added acetic anhydride (158 mg, 1.54 mmol) dropwise at 0° C.The mixture was stirred at RT overnight. The solution was quenched withwater and concentrated at a low pressure. The residue was dissolved inEA (10 mL), and washed with brine. The organic layer was dried overanhydrous Na₂SO₄. The organic phase was concentrated at low pressure.The residue was purified by silica gel column (i-PrOH in DCM from 1% to3%) to give crude compound 153 (172 mg). Crude compound 153 was purifiedby prep-HPLC (0.1% HCOOH in water and MeCN) to give pure compound 153(46 mg, 23.8%) as a white solid. ESI-LCMS: m/z 602.3 [M-F]⁺.

Compound 152-C (1.02 g, 23%, a colorless oil) was prepared using aprocedure similar to the preparation of 150-C using 150-A (2.00 g, 13.16mmol) and 4-chlorophenol (1.68 g, 13.16 mmol).

Example 92 Compound 165

To a solution of 165-1 (5 g, 0.02 mol), cyclopentanone (5.25 g, 0.06mol, 4.5 eq.) and trimethoxymethane (6.52 g, 0.06 mol, 3 eq.) in MeCN(80 mL) was added TSOH.H₂O (1.95 g, 0.01 mol). The mixture was heated at80° C. overnight. The mixture was concentrated at low pressure. Theresidue was purified by column chromatography (20% EA in PE) to give165-2 (3.8 g, 60%) as a white oil.

To a solution of 165-2 (5 g, 0.16 mol) in MeCN (50 mL, anhydrous) wasadded IBX (5.33 g, 0.019 mol, 1.11 eq.) at RT. The mixture was heated at80° C. for 5 h. The mixture was cooled to R.T and filtered. The filtratewas concentrated to give 165-3 (4.5 g, purity: 90%).

To a solution of 165-3 (5 g, 0.016 mol) and CH₂O (3.6 mL) in 1,4-dioxane(50 mL) was added NaOH solution (11.3 mL, 2 N) at RT. The mixture wasstirred for 5 h at RT. NaBH₄ (1.48 g, 0.038 mol) was added at 0° C., andstirred for 1 h. The reaction was quenched with H₂O (30 mL) andextracted with EA (3×30 mL). The organic layer was washed by brine,dried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified by column chromatograph (50% EA in PE) to give165-4 (2.1 g, 38%) as a white oil.

To a stirred solution of 165-4 (3 g, 0.0088 mol) and pyridine (3.51 mL,5 eq.) in DCM (27 mL) was added Tf₂O (3.27 mL, 0.019 mol) at −35° C. Themixture was slowly warmed to 0° C. and stirred for 2 h at 0° C. Themixture was washed with sat. NaHCO₃ solution and extracted with DCM(3×30 mL). The organic layer was separated and washed by brine, driedover anhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by column chromatography (5% EA in PE) to give 165-5 (2.65 g,39%) as a white oil.

To a solution of 165-5 (12.3 g, 0.02 mol) in DMF (20 mL) was added NaH(0.977 g, 0.024 mol) at 0° C. The mixture was stirred for 3 h at RT. Themixture was treated with LiCl (2.6 g, 0.062 mol), and then stirred for 2h. The reaction was quenched with H₂O (20 mL) and extracted with EA(3×30 mL). The organic layer was washed with brine, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bycolumn chromatography (20% EA in PE) to give 165-6 (3.11 g, 45%) as awhite oil.

To a solution of 165-6 (12 g, 0.035 mol) in THF (120 mL) was added NaOHsolution (38.8 mL, 0.038 mol) at 0° C., and stirred for 3 h. at RT. Themixture was adjusted to pH=7 with HCl (1.0 N) solution, and extractedwith EA (3×80 mL). The organic layer was washed with brine, dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by column chromatography to give 165-7 (7.58 g, 60%) as a whitesolid.

165-7 (3 g, 8.0 mmol) was co-evaporated with toluene (30 mL). To asolution of 165-7 (3 g), DMAP (100 mg) and TEA (2.5 mL, 2 eq.) in DCM(30 mL) was added Bz₂O (2.01 g, 1 eq.) at 0° C. The mixture was stirredfor 3 h at RT. The reaction was quenched with H₂O, and extracted withDCM (3×30 mL). The DCM layer was dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by columnchromatography (5% EA in PE) to give 165-8 (3.1 g, 80%) as a whitesolid.

To a solution of 165-8 (200 mg, 0.43 mmol) in CH₃CN (2 mL, anhydrous)was added TPSCl (260 mg, 2 eq.), TEA (0.13 mL) and DMAP (106.4 mg, 2eq.). The mixture was stirred for 2 h at RT.

The mixture was treated with NH₃.H₂O (33%, 1.33 mL), and stirred for 2 hat RT. The reaction was quenched with 1 N HCl (30 mL), and extractedwith DCM (3×30 mL). The DCM layer was dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The residue was purified by columnchromatography to give 165-9 (85 mg, 50%) as a white solid.

165-9 (100 mg, 0.216 mmol) was treated with HCOOH (7 mL, 80%), andstirred for 3 h at RT. The mixture was concentrated at low pressure. Theresidue was purified by column chromatography (90% EA in PE) to give165-10 (51 mg, 60%) as a white solid.

165-10 (270 mg, 0.68 mmol) was treated with NH₃ in MeOH (10 mL) at −60°C. The mixture was warmed to RT. The mixture was stirred for 6 h. at RT.The mixture was concentrated at low pressure. The residue was purifiedby reverse HPLC to give 165 (60 mg, 30%) as a white solid.

Example 93 Compound 169

To a solution of 106 (200 mg, 0.67 mmol) in anhydrous pyridine (5 mL)was added TBSCl (120 mg, 0.8 mmol) at RT. The mixture was stirredovernight, and the reaction mixture was diluted with EA. The mixture waswashed with NaHCO₃ aq. solution and brine. The organic layer was dried,filtered and concentrated to give residue, which was purified by silicagel column chromatography (5% MeOH in DCM to 25% MeOH in DCM to give169-1 (153 mg, 55%) as a white solid.

To a solution of 169-1 (54 mg, 0.13 mmol) in anhydrous DCM (2 mL) wasadded collidine (95 μL, 0.78 mmol), DMTrCl (262 mg, 0.78 mmol) and AgNO₃(66 mg, 0.39 mmol) at RT. The mixture was stirred overnight, and thendiluted with DCM (5 mL). The mixture was filtered through a pre-packedcelite funnel, and the filtrate was washed with NaHCO₃ aq. solution, 1.0M citric acid solution and then brine. The organic layer was dried overNa₂SO₄, and concentrated at low pressure to give a residue. The residuewas purified by silica gel column chromatography (25% EA in PE to 100%EA) to give 169-2 (83.5 mg, 63.6%).

To a solution of 169-2 (83 mg, 0.081 mmol) in THF (1 mL), was added a 1Msolution of TBAF in THF (0.122 mL, 0.122 mmol) at ice bath temperature.The mixture was stirred for 1.5 h. The mixture was diluted with EA, andwashed with water and brine. The organic layer was dried andconcentrated to give the crude product, which was purified by silica gelcolumn chromatography (DCM to 5% MeOH in DCM) to give 169-3 (66.6 mg,91%) as a white foam.

169-3 (66.6 mg, 0.074 mmol) was co-evaporated with toluene and THF (3×).Bis(POC)phosphate (33 mg, 0.96 mmol) was added, and then co-evaporatedwith toluene (3×). The mixture was dissolved in anhydrous THF (1.5 mL)and cooled in an ice bath (0 to 5° C.). 3-nitro-1,2,4-triazole (13 mg,0.11 mmol), diisopropylethyl amine (54 μL, 0.3 mmol), and BOP-Cl (28 mg,0.11 mmol) were added successively. The mixture was stirred 2 h at 0 to5° C., diluted with EtOAc, washed with 1.0M citric acid, sat. aq. NaHCO₃and brine, and dried with Na₂SO₄. The residue was purified on silica (10g column) with CH₂Cl₂:i-PrOH (4-10% gradient) to give 169-4 (68 mg, 76%)as a white solid.

169-4 (68 mg, 0.07 mmol) was dissolved in 80% HCOOH. The mixture wasstirred at R.T. for 2 h. The solvents were evaporated at R.T. andco-evaporated with toluene (3×). The residue was dissolved in 50%CH₃CN/H₂O, was purified on a reverse-phase HPLC (C18) using CH₃CN andH₂O. The product was lyophilization to give 169 (4.8 mg, 14%) as a whitefoam. ESI-LCMS: m/z=613.1 [M+H]⁺, 1225.2 [2M+H]⁺.

Example 94 Compound 145

AA-1 (2.20 g, 3.84 mmol) was dissolved in 80% HCOOH (40 mL) at R.T. (18°C.). The mixture was stirred at R.T. for 12 h. The solvent was removedat low pressure. The residue was purified by column chromatography using50% EA in Hexane to give AA-2 (1.05 g, 91.3%) as a white solid.

To a stirred solution of AA-2 (1 g, 3.32 mmol) in anhydrous pyridine (20mL) was added TBSCl (747 mg, 4.98 mmol) and imidazole (451 mg, 6.64mmol) at R.T. (16° C.) under N₂ atmosphere. The mixture was stirred atR.T. for 4 h. The resulting solution was concentrated to dryness underreduced pressure, and the residue was dissolved in EA (100 mL). Thesolution was washed with sat. NaHCO₃ solution and brine, and dried overanhydrous MgSO₄. The solution was concentrated to dryness, and theresidue was purified on a silica gel column using 20% EA in Hexane togive AA-3 (1.4 g, 79.5%) as a white solid.

To a stirred solution of AA-3 (1.50 g, 2.83 mmol, 1.00 eq.) in anhydrousCH₃CN (28 mL) was added TPSCl (1.71 g, 5.80 mmol, 2.05 eq.), DMAP(691.70 mg, 5.66 mmol, 2.00 eq.) and TEA (573.00 mg, 5.66 mmol, 2.00eq.) at RT (15° C.). The mixture was stirred for 2 h. NH₃.H₂O (20 mL)was added, and the mixture was stirred for 3 h. The mixture wasextracted with EA (3×60 mL). The organic phase was washed with brine,dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified on a silica gel column (30% EA in PE) to give AA-4(2.3 g, crude) as a yellow foam.

To a stirred solution of AA-4 (1.90 g, 2.34 mmol) in anhydrous DCM (20mL) was added DMTrCl (1.82 g, 3.49 mmol) and 2,4,6-trimethylpyridine(1.00 g, 8.25 mmol) at RT (15° C.) under N₂ atmosphere. The mixture wasstirred at RT for 12 h. MeOH (20 mL) was added. The mixture wasfiltered, and the filtrate was concentrated to dryness. The residue wasdissolved in EA (80 mL). The solution was washed with brine, dried overanhydrous Na₂SO₄ and concentrated at low pressure. The residue waspurified on a silica gel column (5% MeOH in DCM) to give AA-5 (1.4 g,crude) as a white solid.

AA-5 (2.40 g, 2.60 mmol) was dissolved in TBAF (10 mL, 1M in THF). Themixture was stirred at RT (15° C.) for 30 mins. The mixture wasconcentrated to dryness, and the residue was dissolved in EA (60 mL).The solution was washed with brine, dried over MgSO₄ and concentratedunder reduced pressure. The residue was purified on a silica gel column(5% MeOH in DCM) to give AA (1.50 g, 95.8%) as a white solid. ESI-MS:m/z 625.3 [M+Na]⁺.

To a solution of AA (60.0 mg, 99.57 μmol, 1.00 eq.) in pyridine (1 mL)was added isobutyric anhydride (31.50 mg, 199.13 μmol, 2.00 eq.) in 1portion at RT (15° C.) under N₂ atmosphere. The mixture was stirred atRT for 12 h. The mixture was concentrated, and the residue waspartitioned between EA and water. The combined organic phases werewashed with water and brine, and dried over anhydrous Na₂SO₄. Themixture was filtered, and the filtrate was concentrated to dryness. Theresidue was purified by silica gel chromatography (30% EA in PE) toafford 145-1 (59.00 mg, 79.77%) as a white solid.

145-1 (57.00 mg, 76.74 μmol, 1.00 eq.) was dissolved in 80% CH₃COOH (8mL). The solution was stirred at RT (15° C.) for 12 h. The mixture wasconcentrated to dryness. The residue was purified on a silica gel column(2.5% MeOH in DCM) to give 145 (23.00 mg, 68.05%) as a white foam.ESI-MS: m/z 441.2 [M+H]⁺, 463.2[M+Na]⁺.

Example 95 Compound 170

170-1 was prepared in similar manner as 145-1 using AA (60.00 mg, 99.57mol, 1.00 eq.) in pyridine (1 mL) and propionic anhydride (25.92 mg,199.13 mol, 2.00 eq.). 170-1 (white solid, 56.00 mg, 78.69%).

170 was prepared in similar manner as 145 using 170-1 (54.00 mg, 75.55mol, 1.00 eq.) 170 (white foam, 18.00 mg, 57.78%). ESI-MS: m/z 413.1[M+H]⁺.

Example 96 Compound 171

171-1 was prepared in similar manner as 145-1 using AA (62.00 mg, 102.89mol, 1.00 eq.) in pyridine (1 mL) and pentanoic anhydride (38.32 mg,205.77 mol, 2.00 eq.). 171-1 (white solid, 60.00 mg, 75.65%).

171 was prepared in similar manner as 145 using 171-1 (75.00 mg, 97.30mol, 1.00 eq.) 171 (white foam, 28.00 mg, 61.43%). ESI-MS: m/z 469.2[M+H]⁺.

Example 97 Compound 146

146-2 (40.7 mg, 53%) was prepared in the same manner from 146-1 (50 mg,0.087 mmol) and bis(isopropyloxycarbonyloxymethyl)phosphate (58 mg,0.175 mmol) with DIPEA (75 μL, 0.52 mmol), BOP-Cl (66.2 mg, 0.26 mmol),and 3-nitro-1,2,4-triazole (30 mg, 0.26 mmol) in THF (0.4 mL) in asimilar manner as 169-4.

146-2 (40 mg, 0.045 mmol) was dissolved in anhydrous CH₃CN (0.5 mL), and4N HCl in dioxane (34 μL, 0.135 mmol) was added at 0 to 5° C. Themixture was stirred at RT for 3 h. Anhydrous EtOH (200 μL) was added.The solvents were evaporated at RT and co-evaporated with toluene (3×).The residue was purified on silica (10 g column) with MeOH/CH₂Cl₂ (5-7%gradient) and lypholized give 146 (15.4 mg, 76%) as a white foam.ESI-LCMS: m/z=614.15 [M+H]⁺, 1227.2 [2M+H]⁺.

Example 98 Compound 172

172-1 (100 mg, 0.174 mmol) was co-evaporated with anhydrous pyridine(3×), toluene (3×) and CH₃CN (3×), and dried under high vacuumovernight. 172-1 was dissolved in CH₃CN (2 mL). A proton sponge (112 mg,0.52 mmol), POCl₃ (49 uL, 0.52 mmol) were added at 0 to 5° C. Themixture was stirred for 3 h at 0 to 5° C. to give intermediate 172-2. Tothis solution, L-alanine isopropyl ester hydrochloride (146 mg, 0.87mmol), and TEA (114 uL, 1.74 mmol) were added. The mixture was stirredfor 4 h at 0 to 5 OC. The mixture was stirred 2 h at 0 to 5° C., thendiluted with EtOAc. The mixture was washed with 1.0M citric acid, sat.aq. NaHCO₃ and brine, and dried with Na₂SO₄. The residue was purified onsilica (10 g column) with CH₂Cl₂/MeOH (0-7% gradient) to give 172-3 (67mg, 43.7%) as a white solid.

172-3 (65 mg, 0.074 mmol) was dissolved in anhydrous CH₃CN (0.5 mL), and4N HCl in dioxane (55 μL, 0.22 mmol) was added at 0 to 5° C. The mixturewas stirred at RT for 1.5 h. A second portion of 4N HCl in dioxane (15μL) was added, and the mixture stirred at RT for 2 h. Anhydrous EtOH(300 μL) was added. The solvents were evaporated at RT and co-evaporatedwith toluene (3×). The residue was dissolved in 50% CH₃CN/H₂O, waspurified on a reverse-phase HPLC (C18) with CH₃CN and water, andlyophilized to give 172 (9 mg, 20%) as a white foam. ESI-LCMS:m/z=608.15 [M+H]⁺, 1215.3 [2M+H]⁺.

Example 99 Compound 173

A solution of 173-1 (4.7 g, 11.2 mmol; prepared according to theprocedure Villard et al., Bioorg. Med. Chem. (2008) 16:7321-7329) andEt₃N (3.4 mL, 24.2 mmol) in THF (25 mL) was added dropwise over 1 h to astirred solution of N,N-diisopropylphosphorodichloridite (1.0 mL, 5.5mmol) in THF (35 mL) at −75° C. The mixture was stirred at RT for 4 h.The mixture was filtered, and the filtrate concentrated. The oilyresidue was purified on silica gel column with EtOAc/hexanes (2-20%gradient) to give 173-3 (1.4 g, 26%).

To a solution of 173-2 (50 mg, 0.08 mmol) and 173-3 (110 mg, 0.11 mmol)in CH₃CN (1.0 mL) was added 5-(ethylthio)tetrazole (0.75 mL, 0.16 mmol;0.25 M in CH₃CN). The mixture was stirred at RT for 1 h. The mixture wascooled to −40° C., and a solution of 3-chloroperoxybenzoic acid (37 mg,0.16 mmol) in CH₂Cl₂ (0.3 mL) was added. The mixture was warmed to RTover 1 h. The reaction was quenched with 7% Na₂S₂O₃ solution in sat aq.NaHCO₃. The mixture was diluted with EtOAc, and the layers wereseparated. The organic layer was washed with brine and dried withNa₂SO₄. The solvent was evaporated, and the residue was purified on asilica gel column with EtOAc/hexanes (30-100% gradient) to give 173-4(52 mg, 45%).

A solution of 173-4 (52 mg, 0.036 mmol) in MeCN (0.5 mL) and HCl (45 μL;4 N in dioxane) was stirred 20 h at RT. The reaction was quenched withMeOH, and the solvents were evaporated. The residue was co-evaporatedwith toluene and purified on a silica gel column with MeOH/CH₂Cl₂ (4-10%gradient) to give 173 (14 mg, 51%). ESI-LCMS: m/z=702 [M+H]⁺.

Example 100 Compound 174

A mixture of 174-1 (0.14 g, 0.24 mmol; prepared according to theprocedure described in WO 2008/082601, filed Dec. 28, 2007) and 173-2(120 mg, 0.2 mmol) was rendered anhydrous by evaporating with pyridineand then dissolved in pyridine (3 mL). Pivaloyl chloride (48 μL) wasadded dropwise at −15° C. The mixture was stirred at −15° C. for 2 h.The reaction was quenched with sat. aq. NH₄Cl solution and diluted withCH₂Cl₂. The organic layer was washed with brine and dried with Na₂SO₄.The solvents were evaporated, and the residue was purified on a silicagel column with EtOAc/hexanes (30-100% gradient) to give 174-2 (50 mg,24%).

A mixture of 174-2 (43 mg; 0.04 mmol) in CCl₄ (0.8 mL), L-valineisopropyl ester hydrochloride (20 mg, 0.12 mmol) and Et₃N (33 μl, 0.24mmol) was stirred at RT for 2 h. The mixture was diluted with EtOAc. Themixture was washed with sat. aq. NaHCO₃ and brine, and dried withNa₂SO₄. The solvents were evaporated, and the residue was purified on asilica gel column with i-PrOH/CH₂Cl₂ (2-10% gradient) to 174-3 (35 mg,75%).

A solution of 174-3 (35 mg, 0.03 mmol) in MeCN (0.4 mL) and HCl (40 μL;4 N in dioxane) was stirred 4 h at RT. The reaction was quenched withthe addition of MeOH, and the solvents were evaporated. The residue wasco-evaporated with toluene and purified on a silica gel column withMeOH/CH₂Cl₂ (4-10% gradient) to give 174 (11 mg, 56%). ESI-LCMS: m/z=655[M+H]⁺.

Example 101 Compound 175

To a stirred solution of AA (300.0 mg, 497.83 mol) in anhydrous pyridine(0.5 mL) was added DMTrCl (337.36 mg, 995.66 mol) at RT (17° C.) underN₂ atmosphere. The solution was stirred at 50° C.˜60° C. for 12 h. Themixture was concentrated to dryness under reduced pressure, and theresidue was dissolved in EA (40 mL). The solution was washed with brine,dried over anhydrous MgSO₄, and concentrated to dryness at low pressure.The residue was purified on a silica gel column using 20% EA in PE togive 175-1 (300 mg, 66.59%) as a white solid.

To a stirred solution of 175-1 (100.00 mg, 110.50 μmol) in anhydrouspyridine (0.5 mL) was added DMAP (6.75 mg, 55.25 μmol), DCC (22.80 mg,110.50 μmol) and n-octanoic acid (31.87 mg, 221.00 μmol) at RT (18° C.)under N₂ atmosphere. The solution was stirred at RT for 12 h. Thesolution was concentrated to dryness under reduced pressure. The residuewas purified on a silica gel column using 15% EA in PE to give 175-2(98.00 mg, 86.0%) as a white foam.

175-2 (90.00 mg, 87.28 μmol) was dissolved in 80% CH₃COOH (20 mL) at RT(16° C.). The mixture was stirred RT for 12 h. The reaction was quenchedwith MeOH, and the mixture was concentrated to dryness. The residue waspurified on a silica gel column (5% MeOH in DCM) to give 175 (33.00 mg,88.7%) as a white solid. ESI-MS: m/z 427.2 [M+H]⁺.

Example 102 Compound 176

To a stirred solution of BB-1 (500.00 mg, 0.87 mmol) in anhydrouspyridine (1 mL) was added TBSCl (236.5 mg, 1.57 mmol) at 20° C. underN₂. The solution was stirred at 50° C.˜60° C. for 12 h. The solution wasconcentrated to dryness under reduced pressure. The residue wasdissolved in EA (50 mL). The solution was washed with sat. NaHCO₃solution and brine, and dried over anhydrous MgSO₄. The solution wasfiltered, and the filtrate was concentrated to dryness. The residue waspurified on a silica gel column to give BB-2 (510.00 mg, 85.06%) as awhite solid.

To a stirred solution of BB-2 (430.00 mg, 625.15 mmol) in anhydrous MeCN(6 mL) was added TPSCl (368.65 mg, 1.25 mmol), DMAP (152.75 mg, 1.25mmol) and TEA (126.52 mg, 1.25 mmol) at RT. The mixture was stirred for2 h. NH₄OH (8 mL) was added, and the mixture stirred for 3 h. Themixture was extracted with EA (3×40 mL). The organic phase was washedwith brine, dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified on a silica gel column (25% EA in PE)to give BB-3 (500 mg of crude) as a yellow foam.

To a stirred solution of BB-3 (500 mg of crude, 0.72 mmol) in anhydrousDCM (7 mL) was added DMTrCl (365 mg, 1.0 mmol) and collidine (305 mg,2.5 mmol) and AgNO₃ (184 mg, 1.08 mmol) at RT (15° C.) under N₂atmosphere. The mixture was stirred at RT for 12 h. MeOH (5 mL) wasadded. The mixture was filtered, and the filtrate was concentrated todryness. The residue was dissolved in EA (50 mL). The solution waswashed with brine, dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified on a silica gel column (5% MeOH inDCM) to give BB-4 (500 mg, 70.3%) as a white solid.

BB-4 (1.00 g, 1.01 mmol) was dissolved in TBAF (5 mL, 1M in THF) andstirred at RT for 30 mins. The mixture was diluted with EA (100 mL). Themixture was washed with water and brine, and dried over anhydrous MgSO₄.The organic phase was concentrated to dryness. The residue was purifiedon the silica gel column (30% EA in PE) to give BB (0.80 g, 91.5%) as awhite solid. ESI-MS: m/z 873.7 [M+1]⁺.

To a solution of BB (100.00 mg, 114.29 mol) in anhydrous pyridine (1.5mL) was added DMAP (2.79 mg, 22.86 mol), DCC (70.75 mg, 342.88 mol) andn-octanoic acid (49.45 mg, 342.88 mol) at RT (18° C.) under N₂atmosphere. The solution was stirred at RT for 12 h. The solution wasconcentrated to dryness under reduced pressure. The residue was purifiedon a silica gel column using 15% EA in PE to give 176-1 (95.00 mg,83.03%) as a white foam.

176-1 (110.00 mg, 109.87 μmol) was dissolved in 80% CH₃COOH (25 mL) atRT (15° C.). The mixture was stirred for 12 h. The reaction was quenchedwith MeOH, and the solution was concentrated to dryness. The residue waspurified on a silica gel column (5% MeOH in DCM) to give 176 (30.00 mg,64.03%) as a white solid. ESI-MS: m/z 427.2 [M+H]⁺.

Example 103 Compound 177

177-1 was prepared in similar manner as 143-1 using BB (250.0 mg, 276.25mol), (2S)-2-(tert-butoxycarbonylamino)-3-methyl-butanoic acid (360.11mg, 1.66 mmol) and TEA (83.86 mg, 828.75 mol). 177-1 (white foam, 220.0mg, 72.12%).

177-2 was prepared in similar manner as 143-2 using 177-1 (230.00 mg,208.29 mol, 1.00 eq.). 177-2 (white foam, 80.00 mg, 77.66%).

177 was prepared in similar manner as 143 using 177-2 (100.00 mg, 200.20mol, 1.00 eq.). 177 (white solid, 56 mg, 59.57%). ESI-MS: m/z 400.0[M+H]⁺, 422.1 [M+Na]+; 799.1 [2M+H]⁺, 821.2 [2M+Na]⁺.

Example 104 Compound 178

To a stirred solution of 178-1 (100 mg, 0.175 mmol) in anhydrous CH₃CN(2.0 mL) was added N-methylimidazole (0.14 mL, 1.4 mmol) at 0° C.(ice/water bath). A solution of 178-2 (220 mg, 0.53 mmol, dissolved in0.5 mL of CH₃CN), (prepared according to a general procedure describedin Bondada, L. et al., ACS Medicinal Chemistry Letters (2013)4(8):747-751) was added. The solution was stirred at 0 to 5° C. for 1 hand then stirred at RT for 16 h. The mixture was cooled to 0 to 5° C.,diluted with EA followed by addition of water (5 mL). The solution waswashed with 1.0M citric acid, sat. aq. NaHCO₃ and brine, and dried withMgSO₄. The residue was purified on silica (10 g column) with EA/hexanes(25-100% gradient) to give 178-3 (56.4 mg, 33.7%) as a white foam.

178-3 (56 mg, 0.0585 mmol) was dissolved in anhydrous CH₃CN (0.7 mL),and 4N HCl in dioxane (44 μL, 0.176 mmol) was added at 0 to 5° C. Themixture was stirred at RT for 2 h. 4N HCl in dioxane (20 μL) was added.The mixture was stirred at RT for 2 h. Anhydrous EtOH (100 μL) wasadded. The solvents were evaporated at RT and co-evaporated with toluene(3×). The residue was purified on silica (10 g column) with MeOH/CH₂Cl₂(1-7% gradient) and lypholized to give 178 (27.6 mg, 69%) as a whitefoam. ESI-LCMS: m/z=685.2[M+H]⁺.

Example 105 Compound 179

To a stirred solution of 179-1 (1.92 g, 27.3 mmol), PPh₃ (1.43 g, 54.7mmol), EtOH (0.25 g, 54.7 mmol) in anhydrous dioxane (20 mL) was addedDIAD (1.11 g, 54.7 mmol) dropwise at 0° C. The solution was stirred at25° C. for 15 h. The reaction was quenched with water and extracted withEA. The mixture was washed with water and brine. The organic layer wasdried over Na₂SO₄ and filtered. The filtrate was concentrated in vacuumto dryness, and the residue was purified on a silica gel column (2% to5% MeOH in DCM) to give 179-2 (1.43 g, 71%) as a white foam.

To a stirred solution of 179-2 (1.43 g, 19.6 mmol) in DMF (15 mL) wasadded TEA (0.59 g, 58.8 mmol) and DMTrCl (0.99 g, 29.4 mmol) at 0° C.The solution was stirred at 25° C. for 12 h. The mixture was treatedwith MeOH (1 mL), and diluted with EA. The solution was washed withwater and brine. The organic layer was dried over anhydrous NaSO₄, andconcentrated to dryness. The residue was purified on a silica gel column(2% MeOH in DCM) to give 179-3 (1.13 g, 56%) as a yellow solid.

To a stirred solution of 179-3 (1.13 g, 1.1 mmol) in anhydrous pyridine(10 mL) was added TBDPSCl (0.91 g, 3.3 mmol) and AgNO₃ (0.61 g, 3.3mmol). The mixture was stirred at 25° C. for 15 h. The solid was removedby filtration, and the filtrate was diluted with EA (50 mL). Thesolution was washed with brine. The organic layer was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified on a silica gel column (2% MeOH in DCM) to give 179-4 (1.22 g,88%) as a white foam.

To a stirred solution of 179-4 (1.22 g, 1.0 mmol) in anhydrous DCM (15mL) was added Cl₂CHCOOH (0.6 mL) at −78° C. The mixture was stirred at−20° C. for 1 h. The reaction was quenched with sat. aq. NaHCO₃ andextracted with DCM. The organic layer was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The residue was purified by columnchromatography (2% MeOH in DCM) to give 179-5 (0.52 g, 56%) as a whitefoam.

To a stirred solution of 179-5 (0.52 g, 0.5 mmol) in anhydrous DCM (15mL) and pyridine (0.21 g, 2.5 mmol) was added Tf₂O (0.30 g, 1.0 mmol) inDCM (1 mL) dropwise at 0° C. The mixture was stirred at 0° C. for 15mins. The reaction was quenched with ice water. The organic layer wasseparated and washed with water. The organic layer was dried overanhydrous Na₂SO₄ and concentrated at low pressure to give 179-6 (442 mgcrude) as a yellow foam.

To a stirred solution of 179-6 (442 mg, 0.4 mmol) in anhydrous DMF (5mL) was added NaN₃ (131 mg, 2.0 mmol). The mixture was stirred at RT for12 h. The reaction was quenched with water and extracted by EA (20 mL,2×). The organic layer was washed with water and dried over Na₂SO₄. Theorganic phase was evaporated to dryness under reduced pressure. Theresidue was purified on a silica gel column (1% MeOH in DCM) to give179-7 (352 mg, 88%) as a white foam.

A mixture of 179-7 (352 mg, 0.35 mmol) and NH₄F (392 mg, 10.6 mmol) inMeOH (10 mL) was stirred at 80° C. for 12 h. The mixture was cooled toRT. The solid was removed by filtration. The solvent was concentratedunder reduced pressure. The residue was purified on a silica gel column(2% to 5% MeOH in DCM) to give crude 179-8 (151 mg). The crude productwas purified by prep-HPLC (0.1% NH₄HCO₃ in water and CH₃CN) to give179-8 (71.5 mg, 32%) as a white solid. MS: m/z 641[M+H]⁺.

A mixture of 179-8 (64 mg, 0.1 mmol) andbis(pivaloyloxymethyl)phosphate, after rendered anhydrous by evaporatingwith toluene, was dissolved in CH₃CN (1 mL) and cooled to 0° C. BopCl(40 mg, 0.15 mmol) and NMI (40 μL, 0.5 mmol) were added. The mixture wasstirred at 0° C. for 2 h. EtOAc was added, and the mixture was washedwith 0.5 N aq. citric acid, sat. aq. NaHCO₃ and brine, and then driedwith Na₂SO₄. The solvents were removed, and the residue was purified ona silica gel column with 3% i-PrOH in CH₂Cl₂ to 179-9 (38 mg, 40%).

A solution of 179-9 (30 mg, 0.03 mmol) in CH₃CN (0.3 mL) and HCl (30 μL;4 N dioxane) was stirred at RT for 100 mins. The reaction was quenchedwith EtOH, and the mixture was evaporated. The crude residue waspurified on a silica gel column with i-PrOH/CH₂Cl₂ (3-10% gradient) toyield 179 (10 mg, 50%). ESI-LCMS: m/z=681 [M+H]⁺.

Example 106 Compound 180

To a solution of BB (100 mg, 0.114 mmol) in anhydrous CH₃CN (2 mL) wereadded a solution of bis-SATE-phosphoroamidate (62.2 mg, 0.14 mmol) inCH₃CN (1 mL) followed by 5-ethylthio-1H-tetrazole in CH₃CN (0.25M; 0.56mL, 0.14 mmol) at 0 to 5° C. dropwise. The mixture was stirred 2 h at 0to 5° C. under Ar. A solution of 77% m-CPBA (49 mg, 0.22 mmol) in DCM (1mL) was added, and the mixture was stirred 2 h at 0 to 5° C. under Ar.The mixture was diluted with EtOAc (50 mL), washed with 1.0M citricacid, sat. NaHCO₃, and brine, and dried with MgSO₄. The mixture wasfiltered and the solvents were evaporated in vacuo. The residue waspurified on silica (10 g column) with EA/hexanes (10-100% gradient) togive 180-1 (72 mg, 50.8%) as a white solid.

180-1 (72 mg, 0.056 mmol) was dissolved in anhydrous CH₃CN (1.0 mL), and4N HCl in dioxane (87 μL, 0.35 mmol) was added at 0 to 5° C. The mixturewas stirred at RT for 2 h. Intermediate 180-2 was observed by LCMS. Thesolvents were evaporated at RT and co-evaporated with toluene (3×). Theresidue obtained was re-dissolved in 80% HCOOH (2 mL). The mixture wasstirred at RT for 4.5 h. The solvents were evaporated at RT andco-evaporated with toluene (3×). Anhydrous EtOH (3×5 mL) was added. Theresidue was dissolved in 50% CH₃CN/H₂O, purified on a reverse-phase HPLC(C18) using CH₃CN and H₂O, and lyophilized to give 180 (19.2 mg) as awhite foam. ESI-LCMS: m/z=669.2 [M+H]⁺, 1337.25 [2M+H].

Example 107 Compound 181

181-1 (98 mg, 72.6%) was prepared in the same manner from BB (100 mg,0.114 mmol) and bis(tert-butoxycarbonyloxymethyl)phosphate (83 mg, 0.35mmol) with DIPEA (126 μL, 0.69 mmol), BOP-Cl (87 mg, 0.34 mmol), and3-nitro-1,2,4-triazole (39 mg, 0.34 mmol) in THF (1.5 mL) in the samemanner as 169-4.

181 (30.2 mg, 60%) was prepared from 181-1 (98 mg, 0.083 mmol) in thesame manner as 146. ESI-LCMS: m/z=609.15 [M+H]⁺, 1217.3 [2M+H]+.

Example 108 Compounds 182 and 183

Compounds 182, 182aa, 182ab and 183 were prepared as described in PCTPublication No. WO 2014/96680, published Jun. 27, 2014. 182: ESI-LCMS:m/z 554.0 [M+H]⁺; 182aa and 182ab: Faster eluting diastereomer—³¹P NMR67.1, LC/MS 552 [M−1]. Slower eluting diastereomer—³¹P NMR 67.9, LC/MS552 [M−1]. 183: ESI-MS: m/z 576.9 [M+H]⁺.

Example 109 Compounds 186-201

Compounds 186-201 were prepared as described in PCT Publication No. WO2014/96680, published Jun. 27, 2014. 186: ESI-LCMS: m/z 593.0 [M+H]⁺.187: ESI-LCMS: m/z 614.1 [M+H]⁺. 188: ESI-LCMS: m/z 582.1 [M+H]⁺. 189:ESI-LCMS: m/z 596.1 [M+H]⁺. 190: ESI-LCMS: m/z 672.0 [M+H]⁺. 191:ESI-LCMS: m/z 589.0 [M+H]⁺. 192: ESI-LCMS: m/z 606.0 [M+H]⁺. 193:ESI-LCMS: m/z 604.1 [M+H]⁺. 194: ESI-LCMS: m/z 568 [M+H]⁺, 590 [M+Na]⁺.195: ESI-LCMS: m/z 680 [M+H]⁺. 196: ESI-LCMS: m/z 578.0 [M+Na]⁺. 197:ESI-MS: m/z 633.1 [M+H]⁺. 198: ESI-LCMS: m/z 604 [M+Na]⁺, 582 [M+H]⁺.199: ESI-LCMS: m/z 582.0 [M+H]⁺. 200: ESI-LCMS: m/z 618 [M+Na]⁺. 201:ESI-LCMS: m/z 568.1 [M+H]⁺.

Example 110 Compound 204

A method for preparing compound 204 is provided in WO 2010/015643, filedAug. 4, 2009.

Example 111 Compound 206

206-1 (1.0 g, 3.53 mmol) was coevaporated with anhydrous pyridine 3times to remove H₂O. To an ice-cold solution of 206-1 in anhydrouspyridine (9 mL) was added TsCl (808 mg, 4.24 mmol) in pyridine (3 mL)drop-wise at 0° C., and the mixture was stirred for 18 h. at 0° C. Thereaction was monitored by LCMS, and then quenched with H₂O. Afterconcentration at low pressure, the residue was dissolved in EA (50 mL).The solution was washed with sat. NaHCO₃ solution and brine. The organiclayer was dried over anhydrous Na₂SO₄ and filtered. The filtrate wasevaporated at low pressure, and the residue was purified by silica gelcolumn chromatography (1% MeOH in DCM) to give 206-2 (980 mg, 63%) as awhite solid.

To a solution of 206-2 (980 mg, 2.24 mmol) in acetone (10 mL) was addedNaI (1.01 g, 6.73 mmol), and the mixture was heated to reflux overnight.The reaction was monitored by LCMS. After the reaction was completed,the mixture was concentrated at low pressure. The residue was dissolvedin EA (50 mL). The solution was washed with brine, and dried overanhydrous Na₂SO₄. The solution was evaporated at low pressure, and theresidue was purified by silica gel column chromatography (1% MeOH inDCM) to give 206-3 (700 mg, 79%) as a solid.

To a solution of 206-3 (700 mg, 1.78 mmol) in dry THF (9 mL) was addedDBU (817 mg, 5.34 mmol), and the mixture was heated to 60° C. Themixture was stirred overnight, and monitored by LCMS. The reaction wasquenched with sat. NaHCO₃ and extracted with EA (3×50 mL). The organicphase was dried over anhydrous Na₂SO₄, and filtered. The filtrate wasevaporated at low pressure, and the residue was purified by silica gelcolumn chromatography (1% MeOH in DCM) to give 206-4 (250 mg, 53%) as awhite solid.

To an ice-clod solution of 206-4 (250 mg, 0.94 mmol) in dry MeCN (5 mL)was added NEt₃.3HF (151 mg, 0.94 mmol) and NIS (255 mg, 1.13 mmol). Themixture was stirred at RT, for 3 h., and checked by LCMS. The reactionwas quenched with sat Na₂S₂O₃ and sat. NaHCO₃ solution, and extractedwith EA (3×50 mL). The organic layer was separated, dried over anhydrousNa₂SO₄, and evaporated at low pressure. The residue was purified bysilica gel column chromatography (2% acetone in DCM) to give 206-5 (170mg, 44%).

To a solution of 206-5 (270 mg, 0.65 mmol) in dry DCM (4 mL) was addedDMAP (158.6 mg, 1.3 mmol), and BzCl (137 mg, 0.98 mmol). The mixture wasstirred for 4-5 h. at RT, and checked by LCMS. The mixture was dilutedwith CH₂Cl₂, and washed with sat. NaHCO₃ solution and brine. The organiclayer was evaporated at low pressure, and the residue was purified bysilica gel column chromatography (20% EA in PE) to give 206-6 (290 mg,86%) as a solid.

To a solution of 206-6 (900 mg, 1.74 mmol) in dry DMF (45 mL) was addedNaOBz (2.5 g, 17.4 mmol) and 15-crown-5 (4.5 g, 20.9 mmol). The mixturewas stirred for 48 h at 90-100° C. The mixture was diluted with EA (100mL), and washed with brine. The organic layer was evaporated at lowpressure, and the residue was purified by silica gel columnchromatography (20% EA in PE) to give 206-7 (500 mg, 56%) as a solid.

To a solution of 206-7 (500 mg, 0.98 mmol) in anhydrous CH₃CN (5 mL) wasadded TPSCl (741 mg, 2.45 mmol), DMAP (299.6 mg, 2.45 mmol) and NEt₃(248 mg, 2.45 mmol) at RT, and the mixture was stirred overnight. Themixture was then treated with NH₃ in THF (5 mL) and then stirred foranother 30 mins. The mixture was diluted with EA (100 mL). The solutionwas washed with 0.5% AcOH solution. The organic solvent was dried overanhydrous MgSO4, and concentrated at low pressure. The crude product waspurified by silica gel column chromatography (2% Acetone in DCM) to give206-8 (257 mg, 51.6%) as a white solid. ESI-MS: m/z 509 [M+H]⁺.

206-8 (80 mg, 0.16 mmol) was dissolved in n-butylamine (3 mL). Themixture was kept overnight at RT and evaporated. The residue wascrystallized from methanol to give 206 (30 mg). The mother liquor waspurified by RP HPLC on Synergy 4 micron Hydro-RP column (Phenominex). Alinear gradient of methanol from 0 to 30% in 50 mM triethylammoniumacetate buffer (pH 7.5) was used for elution. The correspondingfractions were combined, concentrated and lyophilized 3 times to removeexcess of buffer to yield additional 206 (13 mg). 206 (total yield 43mg, 73%). MS: m/z 299.7 [M−1]⁻.

Example 112 Compound 207

207-1 (30 mg, 0.1 mmol) was dissolved in a mixture of CH₃CN (2 mL) andN-methylimidazole (200 uL). Phosphorochloridate (100 mg, 0.3 mmol) wasadded, and the mixture was kept for 5 d at RT. The mixture wasdistributed between water and EA. The organic layer was separated,washed with brine, dried and evaporated. The phosphoroamidate wasisolated by silica gel chromatography in a gradient of methanol in DCMfrom 3% to 10%. The corresponding fractions were concentrated andre-purified by RP HPLC on Synergy 4 micron Hydro-RP column (Phenominex).A linear gradient of methanol in DCM from 3% to 95% containing 0.1%formic acid was used for elution. 207 was obtained as a mixture Rp andRs isomers (9 mg, 16%). MS: m/z 562.1[M−1]⁻.

Example 113 Compound 211

To a solution of 211-1 (23.0 g, 39.5 mmol) in anhydrous toluene (200 mL)was added DAST (31.9 g, 198 mmol) dropwise at −78° C., and the solutionwas stirred at −78° C. for 3 h. The mixture was quenched with sat.NaHCO₃, extracted with EA (2×200 mL) and dried over with anhydrousNa₂SO₄. The solution was concentrated to dryness under low pressure. Theresidue was purified on a silica gel column (50% EA in PE) to give 211-2(16.5 g, 71%) as a yellow foam.

A mixture of 211-2 (16.0 g, 27.4 mmol) and NH₄F (3.0 g, 82.2 mmol) inmethanol (100 mL) was stirred at 70° C. for 12 h. The reaction wascooled, and the salt was removed by filtration. The filtrate wasconcentrated to dryness at low pressure. The residue was purified on asilica gel column (3% MeOH in DCM) to give 211-3 (5.1 g, 69.0%) as awhite foam.

To a stirred suspension of 211-3 (4.1 g, 15.2 mmol), PPh₃ (8.0 g, 30.4mmol), imidazole (2.1 g, 30.4 mmol) and pyridine (18.2 mL) in anhydrousTHF (40 mL) was added dropwise a solution of I₂ (5.8 g, 22.8 mmol) inTHF (20 mL) at 0° C. The mixture was stirred at RT for 12 h. Thereaction was quenched with MeOH (100 mL), and the solvent was removedunder reduced pressure. The residue was purified on a silica gel column(4% MeOH in DCM) to give pure 211-4 (4.4 g, 77%) as a white solid.ESI-MS: m/z 381.1 [M+1]⁺.

To a stirred solution of 211-4 (2.5 g, 0.7 mmol) in anhydrous THF (3 mL)was added DBU (2.1 g, 14 mmol) at RT, and the mixture was stirred at RTfor 1 h. The reaction was quenched with HOAc, and diluted with2-Me-tetrahydrofuran. The solution was washed with brine, dried overwith anhydrous Na₂SO₄ and concentrated to dryness at low pressure. Theresidue was purified on a silica gel column (MeOH 5% in DCM) to give211-5 (1.1 g, 68.9%) as a white foam.

To a stirred solution of 211-5 (800 mg, 3.17 mmol) in anhydrous CH₃CN(10 mL) was added TEA.3HF (510 mg, 3.17 mmol) and NIS (785 mg, 3.49mmol) at 0° C. The mixture was stirred for 30 mins, gradually warmed toRT, and stirred for 1 h. The mixture was quenched with sat. NaHCO₃solution and Na₂S₂O₃ solution, and extracted with EA (2×20 mL). Theorganic layer was dried over with anhydrous Na₂SO₄, and concentrated todryness at low pressure. The residue was purified on a silica gel columnto give pure 211-6 (695 mg, 57.9%) as a yellow solid.

To a stirred solution of 211-6 (650 mg, 1.63 mmol) in pyridine (3 mL)was added BzCl (507 mg, 3.59 mmol) at 0° C., and stirred at RT for 12 h.The mixture was quenched with water, and concentrated to dryness underreducing pressure. The residue was purified on a silica gel column (EA50% in PE) to yield 211-7 (550 mg, 67%) as a white foam.

Tetra-butylammonium hydroxide (9 mL as 54-56% aqueous solution, 72 mmol)was neutralized with TFA to pH-4 (1.5 mL), and the mixture was added toa solution of 211-7 (375 mg, 0.75 mmol) in DCM (9 mL).m-Chloroperbenzoic acid (924 mg, 60-70%, 3.75 mmol) was added inportions with vigorous stirring, and the mixture was stirred overnight.The mixture was washed with brine, dried over magnesium sulfate andconcentrated under reduced pressure. The residue was purified by columnchromatography (EA 50% in PE) to give 211-8 (230 mg, 78.8%) as a whitefoam. ESI-MS: m/z 393.1 [M+1]⁺.

211-8 (120 mg, 0.24 mmol) was treated with 7N NH₃.MeOH (20 mL), andstirred for 5 h. The mixture was concentrated to dryness at lowpressure. The residue was purified on a silica gel column (propan-2-ol15% in DCM) to yield 211 (53 mg, 60.2%) as a white solid. ESI-MS: m/z288.8 [M+1]⁺.

Example 114 Compounds 212a AND 212b

To a solution of 212-1 (0.47 g, 0.65 mol) in DCM (3 mL) was added AgNO₃(0.22 g, 1.29 mmol), collidine (0.15 g, 1.29 mmol) and MMTrCl (0.3 g,0.974 mmol) at 0° C. The mixture was stirred at RT overnight. Themixture was filtered, and the filter was washed with sat. aq. NaHCO₃solution and brine. The organic layer was separated, dried overanhydrous Na₂SO₄ and concentrated at low pressure. The residue waspurified by silica gel column to give 212-2 (0.55, 85%) as a whitesolid.

To a solution of 212-2 (0.5 g, 0.5 mmol) in dry DMF (10 mL) was addedNaOBz (0.72 g, 5 mmol) and 15-crown-5 (0.9 mL). The mixture was stirredat 95° C. for 72 h. The mixture was diluted with EA, and washed withwater and brine. The organic phase was dried over MgSO₄ and concentratedat low pressure. The residue was purified by silica gel column (10% EAin PE) to give 212-3 (0.3 g, 60%) as a white solid.

212-3 (0.3 g, 0.3 mmol) in NH₃/MeOH (30 mL) was stirred at RT for 18 h.The mixture was concentrated at low pressure, and the residue waspurified by silica gel column (20% EA in PE) to give 212-4 (145 mg, 56%)as a white solid. ESI-LCMS: m/z 890.5 [M+H]⁺.

To a stirred solution of 212-4 (161 mg, 0.16 mmol) in anhydrous CH₃CN(2.0 mL) was added N-methylimidazole (118 μL, 2.87 mmol) at 0 to 5° C.(ice/water bath) followed by solution of 212-5 (186 mg, 0.54 mmol,dissolved in 2 mL of CH₃CN). The solution was stirred at 0 to 5° C. for4 h. The mixture was diluted with EA, and water was added (15 mL). Thesolution was washed H₂O, 50% aqueous citric acid solution and brine. Theorganic layer was separated, dried over anhydrous MgSO₄ and filtered.The filtrate was concentrated in vacuum to give a residue, which waspurified on silica gel with 0 to 40% EA/hexanes to give as 212-6 (82.6mg) as the faster eluting isomer and 212-7 (106 mg) as the slowereluting isomer.

212-6 (82.6 mg, 0.07 mmol) was dissolved in anhydrous CH₃CN (0.5 mL),and 4N HCl in dioxane (35 μL) was added at 0 to 5° C. The mixture wasstirred at RT for 1 h, and anhydrous EtOH (100 μL) was added. Thesolvents were evaporated at RT and co-evaporated with toluene 3 times.The residue was dissolved in 50% CH₃CN/H₂O, and purified on areverse-phase HPLC (C18) using acetonitrile and water, followed bylyophilization to give 212a (19.4 mg). ESI-LCMS: m/z=655.2 [M+H]⁺,653.15 [M−H]⁻.

212-7 (100 mg, 0.083 mmol) was dissolved in anhydrous CH₃CN (0.5 mL),and 4N HCl in dioxane (50 μL) was added at 0 to 5° C. Following theprocedure for obtaining 212a, 212b (31.8 mg) was obtained. ESI-LCMS:m/z=655.2 [M+H]⁺, 653.1 [M−H]⁻.

Example 115 Compound 213

To a solution of the nucleoside (300 mg, 1.09 mmol) and proton-sponge(467 mg, 2.18 mmol) in anhydrous CH₃CN (5 mL) at 0° C. under N₂ wasadded dropwise a solution of phosphorus oxychloride (330 mg, 2.18 mmol)in anhydrous CH₃CN (1 mL). The mixture was stirred at 0° C. for 30 mins,and the hydrogen chloride salt of (S)-ethyl 2-aminopropanoate (998 mg,6.52 mmol) and triethylamine (1.5 mL, 10.87 mmol) at 0° C. were added.The mixture was stirred overnight at 30° C. The reaction was quenchedwith water, and extracted with EA (3×20 mL). The organic layer wasconcentrated at low pressure, and the residue was purified by reversephase HPLC to give 213 (20 mg, 3%) as a white solid. ESI-LCMS: m/z 535[M-F]⁺.

Example 116 Compound 214

The nucleoside (140 mg, 0.42 mmol) was dissolved in n-butylamine (0.5mL). The mixture was kept for 2 h at RT, and the amine was thenevaporated. The residue was dissolved in EtOAc, and the organic layerwas washed twice with 10% citric acid, dried over Na₂SO₄, andevaporated. The residue purified by column chromatography on silica gelin linear gradient of methanol in DCM from 0% to 12% over 10 columnvolumes. The fractions containing the product were concentrated andtreated with 80% HCOOH for 1 h at RT. The mixture was evaporated todryness, and suspended in CH₃CN. The precipitate was separated, washedwith CH₃CN (1 mL) and dried to yield 214 (27 mg, 50%). MS: m/z 326.5[M−1]⁻.

Example 117 Compound 216

To a solution of 216-1 (3.0 g, 18.0 mmol) and POC₃ (1.35 g, 9.0 mmol) inDCM (80 mL) was added TEA (3.6 g, 36.0 mmol) in DCM (20 mL) dropwise at0° C. The mixture was stirred at 0° C. for 2 h. A solution ofpentafluorophenol (1.65 g, 9.0 mmol) and TEA (0.9 g, 9.0 mmol) in DCM(20 mL) was added dropwise at 0° C., and the mixture was stirred at 0°C. for 15 h. After the reaction was completed, the mixture wasconcentrated under reduced pressure. The residue was washed by TBME andfiltered. The filtrate was concentrated under reduced pressure, and theresidue was purified by silica gel chromatography (20% EA in PE) to give216-2 (2.7 g, 62.7%) as a white solid. ESI-MS: m/z 491.1 [M+1]⁺.

To a stirred solution of1-((3aR,4R,6S,6aS)-6-fluoro-6-(hydroxymethyl)-2-methoxy-3a-methyltetrahydrofuro[3,4-d][1,3]dioxol-4-yl)pyrimidine-2,4(1H,3H)-dione(150 mg, 0.47 mmol) in anhydrous THF (2 mL) was added a solution oft-BuMgCl (0.46 mL, 1M in THF) dropwise at 0° C. The mixture was stirredat RT for 40 mins, and re-cooled to 0° C. A solution of 216-2 (462 mg,0.94 mmol) was added, and the mixture was stirred at RT for 4 h. Themixture was quenched with H₂O, and extracted with EA. The organic layerwas dried over Na₂SO₄ and concentrated under reducing pressure. Theresidue was purified on a silica gel column (50% EA in PE) to give 216-3as a white foam (230 mg, 78%).

216-3 (230 mg, 0.37 mmol) was dissolved in 80% HCOOH aqueous solution(20 mL), and the mixture was stirred at RT for 24 h. The solvent wasremoved at low pressure. The residue was purified on a silica gel columnto give the crude product, which was purified by RP HPLC (HCOOH system)to give 216 as a mixture of two P-isomers (75 mg, 33%). ESI-TOF-MS: m/z583.0 [M+H]⁺.

Example 118 Compound 218

218-1 (30 mg, 0.1 mmol) was dissolved in a mixture of CH₃CN (2 mL) andN-methylimidazole (200 uL). Phosphorochloridate (100 mg, 0.3 mmol) wasadded, and the mixture was kept overnight at 40° C. The temperature wasincreased to 65° C. and heated for 1 h. The mixture was distributedbetween water and EA. The organic layer was separated, washed withbrine, dried and evaporated. The azido-phosphoroamidate was purified byRP HPLC on Synergy 4 micron Hydro-RP column (Phenominex). A lineargradient of methanol from 30% to 100% in 50 mM triethylammonium acetatebuffer (pH 7.5) was used for elution. The azido-phosphoroamidate (8 mg)was dissolved in pyridine/Et₃N (3 mL, 8:1 v/v) and cooled to 0° C. H₂Sgas was bubbled through the solution for 10 mins, and the reaction waskept for 1 h at RT. The solvents were evaporated, and the residueisolated by RP HPLC. The corresponding fractions were combined,concentrated and lyophilized 3 times to remove excess of buffer, toprovide 218 (1.2 mg) as mixture Rp and Rs isomers. MS: m/z 544.1 [M+1]⁺.

Example 119 Compound 219

To a solution of IBX (133.33 g, 476 mmol) in dry CH₃CN (2 μL) was added219-1 (100.0 g, 216 mol) at RT. The mixture was refluxed and stirred for12 h. The mixture was filtered, and the filtrate was concentrated at lowpressure to give 219-2 as a yellow oil (90.0 g, 90.4%).

219-2 (50.0 g, 108.70 mmol) was coevaporated with anhydrous toluenetwice to remove H₂O. Ethynyl magnesium bromide, (800 mL, 400.0 mmol) wasadded dropwise into a solution of 73-2 in THF (500 mL) over 20 mins at−78° C. The mixture was stirred for about 10 mins at −78° C. When thestarting material was consumed, the ice-acetone cooling bath wasremoved. The mixture was quenched with a sat. NH₄Cl solution withstirring, and then warmed to RT. The mixture was extracted with EA,filtered through Celite and washed with brine. The combined organicphase was dried over anhydrous Na₂SO₄, filtered and concentrated at lowpressure to give crude 219-3 as a deep yellow oil (48.0 g, yield:90.8%).

219-3 (200.0 g, 411.52 mmol) was dissolved in anhydrous CH₂Cl₂ (2000 mL)and then DMAP (100.41 g, 823.05 mmol) and Et₃N (124.94 g, 1.23 mol) wereadded at RT. The mixture was treated with benzoyl chloride (173.46 g,1.23 mol) at 0° C. After stirring for 12 h at RT, the reaction wasquenched with H₂O. The combined aq. phase was extracted with DCM. Thecombined organic phase was dried over anhydrous Na₂SO₄, filtered andevaporated to dryness under reduced pressure to give a black oil. Theoil was purified by column chromatography using 7%-20% EA in PE as theeluent to give a yellow oil. The residue triturated with CH₃OH andfiltered. The filter cake was concentrated in vacuo to give 219-4 as awhite solid (30.0 g, 36.4%).

Uracil (34.17 g, 305.08 mmol) were coevaporated with anhydrous toluenetwice to remove H₂O. To a stirred suspension of uracil in anhydrous MeCN(150 mL) was added N,O-BSA (123.86 g, 610.17 mmol) at RT. The mixturewas refluxed for 1.5 h and then cooled to RT. 219-4 (90 g, 152.54 mmol,which were coevaporated with anhydrous toluene twice to remove H₂O) wasadded. TMSOTf (237.05 g, 1.07 mol) was then added at RT. The mixture washeated to 70° C., and then stirred overnight and then monitored by LCMS.The mixture was cooled to RT, and quenched with a sat. NaHCO₃ solution.The solution was extracted with EA. The organic layer was dried overNa₂SO₄, and then concentrated at low pressure. The residue was purifiedusing a silica gel column eluted with 10%-50% EA in PE to give 219-5 asa white solid (45 g, 50.9%).

219-5 (50 g, 86.21 mmol) was treated with NH₃ in MeOH (1 L) at RT, andthen stirred for 48 h. The mixture was concentrated at low pressure, andthe residue was purified by column chromatography (10% MeOH in DCM) togive 219-6 (12.6 g, 54.55%) as a white solid.

To a solution of cyclopentanone (100 g, 1.189 mmol) and trimethylorthoformate (150 mL) in MeOH (600 mL) was added TsOH.H₂O (1.13 g, 5.9mmol), and the mixture was stirred at RT for 30 mins. The reaction wasquenched with NaOMe (0.32 g, 5.9 mmol) and H₂O, and the solution wasextracted by n-hexane. The organic layer was dried over anhydrousNa₂SO₄, and then concentrated at low pressure. The cyclopentyl dimethoxyacetal and 219-6 (20 g, 74.63 mmol) was dissolved in DCE (200 mL), andthen treated with TsOH.H₂O (0.71 g, 3.73 mmol). The mixture was stirredat 50° C. for 12 h, and then concentrated at low pressure. The residuewas purified by silica gel column chromatography (1-10% MeOH in DCM) togive 219-7 (15.4 g, 61.8%) as a white solid.

219-7 (20.0 g, 0.06 mol) was coevaporated with anhydrous pyridine threetimes to remove H₂O. To an ice-cold solution of 219-7 in anhydrouspyridine (100 mL) was added TsCl (22.8 g, 0.12 mol) at 0° C., and themixture was stirred overnight and monitored by LCMS and TLC. Thereaction was quenched with H₂O and extracted with EA. The organic phasewas dried over anhydrous NaSO₄ and evaporated at low pressure. Theresidue was purified by silica gel column chromatography (DCM:MeOH=100:1 to 15:1) to give 219-8 (20.0 g, 69.0%) as a white solid.

To a solution of 219-8 (20.0 g, 0.04 mol) in acetone (200 mL) was addedNaI (31.0 g, 0.2 mol) and heated to reflux overnight and monitored byLCMS. The mixture was quenched with a sat. Na₂S₂O₃ solution, andextracted with EA. The organic phase was dried over anhydrous Na₂SO₄ andevaporated at low pressure. The residue was purified by silica gelcolumn chromatography (DCM: MeOH=100:1 to 15:1) to give 219-9 (15.0 g,83.3%) as a white solid.

To 219-9 (30.0 g, 0.068 mol) in dioxane (60 mL) in sealed tube was addedCuBr (4.9 g, 0.034 mol), i-Pr₂NH (13.6 g, 0.135 mol) and (CH₂O)_(n)(5.1g, 0.17 mol) under N₂. The mixture was heated at reflux for 16 h. Themixture was diluted with EtOAc, and washed with a sat. NH₄Cl solutionand brine. The solution was dried over anhydrous MgSO₄, and concentratedunder reduced pressure. The residue was purified by columnchromatography (DCM: MeOH=100:1 to 15:1) to give 219-10 (10.0 g, 32.3%)as a white solid.

219-10 (10 g, 21.83 mmol) was treated with HCOOH (80%) in H₂O at RT. Thesolution was stirred at 60° C. for 2 h, and then concentrated at a lowpressure. The residue was purified by column chromatography (1%-10% MeOHin DCM) to give 219-11 (5.1 g, 58.55%) as a white solid.

219-11 (5 g, 12.79 mmol) was dissolved in anhydrous MeOH (100 mL) andtreated with NaOMe (4.83 g, 89.5 mmol) at RT. The solution was stirredat 60° C. for 36 h. The mixture was quenched with CO₂ and thenconcentrated at low pressure. The residue was purified by columnchromatography (0-10% MeOH in DCM) to give 219-12 (2.3 g, 68.05%) as ayellow solid. ¹H-NMR (CDCl₃, 400 MHz) δ=7.29 (d, J=8 Hz 1H), 6.10 (s,1H), 5.71 (d, J=8.0 Hz 1H), 5.18 (t, J=6.4 Hz, 1H), 4.79-4.84 (m, 1H),4.61 (d, J=8.0 Hz, 2H), 4.39 (s, 1H), 3.45 (s, 1H).

To an ice-cold solution of 219-12 (1.5 g, 5.68 mmol) in anhydrous MeCN(15 mL) was added NIS (1.66 g, 7.39 mmol) and TEA.3HF (0.73 g, 4.55mmol) under N₂. The mixture was stirred at RT for 1 h. The reaction wasquenched with sat. NaHCO₃ and sat. Na₂SO₃ solution, and extracted withEA (3×100 mL). The organic phase was dried over anhydrous Na₂SO₄, andevaporated to dryness at low pressure. The residue was purified on asilica gel column (0-5% MeOH in DCM) to give 219-13 (1.08 g, 46.2%) as ayellow solid.

To a stirred solution of 219-13 (1 g, 2.44 mmol) in anhydrous DCM (10mL) was added DMAP (0.60 g, 4.88 mmol) and Et₃N (0.74 g, 7.32 mmol) atRT. The mixture was treated with benzoyl chloride (0.79 g, 5.61 mmol) at0° C. and then stirred at RT for 3 h. The reaction was quenched withwater, and extracted with EA (3×60 mL). The organic phase wasconcentrated at low pressure, and the residue was purified by columnchromatography (0-10% MeOH in DCM) to give 219-14 (0.9 g, 59.6%) as awhite solid.

Bu₄NOH (55% in H₂O, 13.74 mL) was treated with TFA (to adjust pH=3-4).The mixture was cooled to RT. To a solution of 219-14 (0.9 g, 1.46 mmol)in DCM (9 mL) was added m-CPBA (80%, 1.57 g, 7.28 mmol) at RT. Themixture was stirred at 25° C. for 48 h. The mixture was washed with sat.aq. NaHCO₃. The organic layer was passed through an anhydrous Al₂O₃column, and the solution was concentrated at low pressure. The residuewas purified by a silica gel column (30% EA in PE) to give 219-15 (0.26g, 35.1%) as a yellow solid.

219-15 (0.25 g, 0.49 mmol) was dissolved in NH₃/MeOH (5 mL, 7 M), andthe mixture was stirred at RT for 24 h under N₂. The mixture wasconcentrated at low pressure at RT, and the residue was purified by asilica gel column (5% MeOH in DCM) to give 219-16 (100 g, 67.75%) as awhite solid. ¹H-NMR (CD₃OD, 400 MHz) δ=7.83 (d, J=8 Hz 1H), 6.29 (s,1H), 5.67 (d, J=6.0 Hz 1H), 5.12 (t, J=6.8 Hz, 1H), 4.99-5.01 (m, 1H),4.38 (d, J=19.6 Hz 1H), 3.74-3.81 (m, 2H), 3.35 (s, 1H).

219-16 (100 mg, 0.33 mmol) was co-evaporated with toluene three times toremove H₂O. To a stirred solution of 219-16 (100 mg, 0.33 mmol) in amixture of MeCN (1.0 mL) and NMI (271 mg, 3.3 mmol) was added a solutionof 219-C (216.5 mg, 0.66 mmol) in MeCN (0.5 mL) at 0° C. The mixture wasstirred at RT overnight and then reaction was quenched with water. Themixture was diluted with EA (20 mL), and the organic layer was washedwith water and brine, and dried over anhydrous Na₂SO₄. The organic phasewas concentrated at low pressure, and the residue was purified on asilica gel column (5% i-PrOH in DCM) to give the crude product. Thecrude product was purified by prep-HPLC (0.1% HCOOH in water and MeCN)to give 219 (35.6 mg, 19.0%) as a white solid. ESI-LCMS: m/z 592[M+Na]⁺.

To a stirred solution of 219-A (2.0 g, 13.16 mmol) and phenol (1.22 g,13.16 mmol) in anhydrous DCM (100 mL) was added a solution of TEA (1.33g, 13.16 mmol) in DCM (20 mL) dropwise at −78° C. The mixture was warmedgradually to RT, and then stirred for 2 h. The solution was re-cooled to−78° C., and (S)-isopropyl 2-aminopropanoate hydrochloride (2.20 g,13.16 mmol) in DCM (20 mL) was added, followed by the dropwise additionof TEA (2.66 g, 26.29 mmol) in DCM (20 mL). The mixture was warmedgradually to RT, and then stirred for 2 h. The organic solvent wasremoved at low pressure, and the residue was dissolved in methyl-butylether. The precipitate was filtered, and the filtrate was concentratedat low pressure. The residue was purified on a silica gel column(anhydrous DCM) to give 219-C (0.9 g, 22.3%) as a colorless oil.

Example 120 Compound 220

Dry nucleoside (0.05 mmol) was dissolved in a mixture of PO(OMe)₃ (0.7mL) and pyridine (0.3 mL). The mixture was evaporated in vacuum for 15mins. at 42° C., then cooled to RT. N-Methylimidazole (0.009 mL, 0.11mmol) was added followed by POCl₃ (0.009 mL, 0.11 mmol). The mixture waskept at RT for 20-40 mins and monitored for the formation of 220 byLCMS. The reaction was quenched with water and isolated by RP HPLC onSynergy 4 micron Hydro-RP column (Phenominex). A linear gradient ofmethanol from 0 to 30% in 50 mM triethylammonium acetate buffer (pH 7.5)was used for elution. The corresponding fractions were combined,concentrated and lyophilized 3 times to remove excess of buffer. MS: m/z396.5 [M−1]⁻.

Example 121 Compound 223

A solution of 223-1 (16.70 g, 0.363 mol) and TEA (36.66 g, 0.363 mol) inCH₂Cl₂ (150 mL) was added dropwise to a stirred solution of POCl₃ (55.65g, 0.363 mol) in DCM (100 mL) over 25 mins at −78° C. After the mixturewas stirred for 2 h. at RT, the triethylamine hydrochloride salt wasfiltered, and washed with CH₂Cl₂ (100 mL). The filtrate was concentratedat low pressure, and the residue was distilled under high vacuum (˜10 mmHg) with a cow-head fraction collector. 223-2 was collected between 45°C. (distillation head temperature) as a colorless liquid (30.5 g, 50%yield). ¹H-NMR (400 MHz, CDCl₃) δ=4.44 (dq, J=10.85, 7.17 Hz, 2H),1.44-1.57 (m, 3H); ³¹P-NMR (162 MHz, CDCl₃) δ=6.75 (br. s., 1P).

To a stirred suspension of 227-A (93 mg, 0.15 mmol) in CH₂Cl₂ (1 mL) wasadded TEA (61 mg, 0.15 mmol) at RT. The mixture was cooled to −20° C.,and then was treated with a 223-2 (35 mg, 0.21 mmol) solution dropwiseover a period of 10 mins. The mixture was stirred at this temperaturefor 15 mins., and then was treated with NMI (27 mg, 0.33 mmol). Themixture was stirred at −20° C., and then slowly warmed to RT. Themixture was stirred overnight. The mixture was suspended in EA (15 mL),washed with brine (10 mL) and dried over anhydrous sodium sulfate. Thesolution was concentrated at low pressure, and the residue was purifiedby chromatography (DCM: MeOH=100:1) to give 223-3 (60 mg, yield: 56%) asa solid.

A solution of 223-3 (60 mg, 0.085 mmol) in 80% AcOH aqueous (2 mL) wasstirred at RT for 2 h. The mixture was concentrated under reducedpressure, and the residue was purified by a silica gel column elutingDCM/MeOH=50/1 and prep-HPLC to give 223 (23 mg, 62%) as a white solid.ESI-MS: m/z 436.3 [M+H]⁺.

Example 122 Compound 224

224-2 was prepared using a similar procedure as for the preparation of223-2 using a solution of iso-butanol (23.9 g, 322.98 mmol) and POCl₃(49.5 g, 322.98 mmol). 224-2 (26 g, 42% yield) was obtained as acolorless liquid. ¹H-NMR (400 MHz, CDCl₃) δ=4.10 (dd, J=9.04, 6.39 Hz,2H), 2.09 (dq, J=13.24, 6.67, 6.67, 6.67, 6.67 Hz, 1H), 1.01 (d, J=6.62Hz, 6H); ³¹P-NMR (162 MHz, CDCl₃) δ=7.06 (br. s., 1P).

To a stirred suspension of 227-A (310 mg, 0.5 mmol) in CH₂Cl₂ (3 mL) wasadded TEA (202 mg, 2 mmol) at RT. The mixture was cooled to −20° C., andthen was treated with 224-2 (134 mg, 0.7 mmol). The mixture was stirredat this temperature for 15 mins and then was treated with NMI (90 mg,1.1 mmol). The mixture was stirred at −20° C. for 1 h., and then slowlywarmed to RT overnight. The mixture was suspended in EA (15 mL), washedwith brine (10 mL), and dried over anhydrous sodium sulfate. The organicphase was concentrated at low pressure, and the residue was purified bysilica column gel (DCM: MeOH=100:1) to give 224-3 (310 mg, yield: 84%)as a solid.

A solution of 224-3 (310 mg, 0.43 mmol) in 80% AcOH aqueous (4 mL) wasstirred at RT for 2 h. The mixture was concentrated at low pressure, andthe residue was purified by a silica gel column eluting DCM/MeOH=50/1and prep-HPLC to give 224 (79 mg, 50%) as a white solid. ESI-MS: m/z464.0 [M+H]⁺.

Example 123 Compound 225

225-2 was prepared using a similar procedure as for the preparation of223-2 using a solution of isopropyl alcohol (21 g, 350 mmol) and POCl₃(53.6 g, 350 mmol). 225-2 (40.5 g, 65% yield) was obtained as acolorless liquid. ¹H-NMR (400 MHz, CDCl₃) δ=4.94-5.10 (m, 1H), 1.48 (d,J=6.17 Hz, 6H); ³¹P-NMR (162 MHz, CDCl₃) δ=5.58 (br. s., 1P).

225-3 was prepared using a similar procedure as for the preparation of224-3 using 225-2 (124 mg, 0.7 mmol) and 227-A (310 mg, 0.5 mmol). 225-3(300 mg, 83%) was obtained as a solid.

225 was prepared using a similar procedure as for the preparation of 224using 225-3 (300 mg, 0.41 mmol) in 80% AcOH aqueous (4 mL). 225 (80 mg,43%) was obtained as a white solid. ESI-MS: m/z 450.0 [M+H]⁺.

Example 124 Compound 227

To a stirred solution of POCl₃ (2.0 g, 13 mmol) in anhydrous DCM (10 mL)was added 1-naphthol (1.88 g, 13 mmol) at −70° C., and TEA (1.31 g, 13mmol) in DCM (3 mL) dropwise at −70° C. The mixture was gradually warmedto RT and stirred for 1 h. Crude 227-1 was obtained.

To a stirred solution of (S)-isopropyl 2-aminopropanoate hydrochloride(2.17 g, 13 mmol) in DCM (10 mL) was added crude 227-1 at −70° C. TEA(2.63 g, 26 mmol) was added to the stirred solution dropwise at −70° C.The mixture was gradually warmed to RT and stirred for 2 h. The reactionwas monitored by LCMS and quenched with n-propylamine. The mixture wasconcentrated at low pressure, and the residue was purified by a silicagel column (PE:MTBE=5:1˜1:1) to give pure 227-2 (1.6 g, 35%).

To a solution of 227-A (300 mg, 0.337 mmol) and NMI (276 mg, 3.37 mmol)in anhydrous CH₃CN (4 mL) was added 227-2 (240 mg, 0.674 mol, in DCM (5mL)) at 0° C. The mixture was stirred at RT for 10 h. The reaction wasmonitored by LCMS. The reaction was quenched with water, and extractedwith CH₂Cl₂ (3×20 mL). The organic phase was dried over anhydrous MgSO4,and concentrated at low pressure. The residue was purified by sil-gel(PE:EA=5:1˜2:1) to give 227-3 (380 mg, 93%).

227-3 (380 mg, 0.314 mmol) was dissolved in CH₃COOH (80%, 8 mL), andstirred at 40-50° C. for 2.5 h. The reaction was monitored by LCMS. Themixture was concentrated at low pressure, and the residue was purifiedby chromatography (PE:EA=1:1˜EA) to give crude 227. The crude productwas purified by prep-HPLC (neutral system, NH₄HCO₃) to give pure 227 (70mg, 80%) as a white solid. ESI-MS: m/z 665.1 [M+H]⁺.

Example 125 Compound 228

To a stirred solution of POCl₃ (2.0 g, 13 mmol) in anhydrous DCM (10 mL)was added 1-naphthol (1.88 g, 13 mmol) at −70° C. and TEA (1.31 g, 13mmol) in DCM (3 mL) dropwise at −70° C. The mixture was gradually warmedto RT, and stirred for 1 h. A crude solution of 228-1 was obtained.

To a stirred solution of (S)-isobutyl 2-aminopropanoate hydrochloride(2.35 g, 13 mmol) in DCM (20 mL) was added TEA (2.63 g, 26 mmol) and acrude solution of 228-1 at −70° C. The mixture was gradually warmed toRT, and stirred for 2 h. The reaction was monitored by LCMS and quenchedwith n-propylamine. The solvent was evaporated at low pressure, and theresidue was purified by chromatography (PE:MTBE=5:1˜1:1) to give pure228-2 (1.8 g, 37%).

To a solution of 227-A (300 mg, 0.337 mmol) and NMI (276 mg, 3.37 mmol)in anhydrous CH₃CN (4 mL) was added 228-2 (249 mg, 0.674 mol, in DCM (5mL)) at 0° C. The mixture was stirred at RT for 10 h. The reaction wasmonitored by LCMS, and then quenched with H₂O. The mixture was extractedwith CH₂Cl₂ (3×20 mL). The organic phase was dried over anhydrous MgSO4,and concentrated at low pressure. The residue was purified bychromatography using PE:EA=5:1˜2:1 as the eluent to give 228-3 (360 mg,87%).

228-3 (360 mg, 0.294 mmol) was dissolved in CH₃COOH (80%, 8 mL), andstirred at 40-50° C. for 2.5 h. The reaction was monitored by LCMS andthen quenched with MeO. The mixture was concentrated at low pressure,and the residue was purified by chromatography using PE:EA=1:1 as theeluent to generate crude 228. The product purified by prep-HPLC (neutralsystem, NH₄HCO₃) to give 228 (70 mg, 75%) as a white solid. ESI-MS: m/z679.2 [M+H]⁺.

Example 126 Compound 229

To a stirred solution of POCl₃ (2.0 g, 13 mmol) in anhydrous DCM (10 mL)was added phenol (1.22 g, 13 mmol) at −70° C. and TEA (1.31 g, 13 mmol)in DCM (3 mL) dropwise at −70° C. The mixture was gradually warmed toRT, and stirred for 1 h. A crude solution of 229-1 was obtained.

229 was prepared using a similar procedure as for the preparation of 228using 229-2 (205 mg, 0.674 mol, in DCM (5 mL) obtained from(S)-isopropyl 2-aminopropanoate hydrochloride and 229-1) and 227-A (300mg, 0.337 mmol). 229 (50 mg, 74%) was obtained as a white solid. ESI-MS:m/z 615.2 [M+H]⁺.

Example 127 Compound 230

230 was prepared using a similar procedure as for the preparation of 228using 230-2 (214 mg, 0.674 mol, in DCM (5 mL) obtained from (S)-isobutyl2-aminopropanoate hydrochloride and 230-1) and 227-A (300 mg, 0.337mmol). 230 (70 mg, 87%) was obtained as a white solid. ESI-MS: m/z 629.2[M+H]⁺.

Example 128 Compound 231

231 was prepared using a similar procedure as for the preparation of 228using 231-2 (223 mg, 0.674 mol, DCM (5 mL) obtained from (S)-cyclopentyl2-aminopropanoate hydrochloride and 231-1) and 227-A (300 mg, 0.337mmol). 231 (62 mg, 71%) was obtained as a white solid. ESI-MS: m/z 641.2[M+H]⁺.

Example 129 Compound 232

232 was prepared using a similar procedure as for the preparation of 228using 232-2 (223 mg, 0.674 mol, DCM (5 mL), obtained from (S)-3-pentyl2-aminopropanoate hydrochloride and 232-1) and 227-A (300 mg, 0.337mmol). 232 (42 mg, 60%) was obtained as a white solid. ESI-MS: m/z 643.2[M+H]⁺.

Example 130 Compound 233

A stirred solution of phosphoryl trichloride (1.00 g, 6.58 mmol) and5-quinoline (955 mg, 6.58 mmol) in anhydrous DCM (50 mL) was treatedwith a solution of TEA (665 mg, 6.58 mmol) in DCM (10 mL) at −78° C. Themixture was gradually warmed to RT, and stirred for 2 h. The solutionwas cooled to −78° C. and then treated with (S)-neopentyl2-aminopropanoate hydrochloride (1.28 g, 6.58 mmol). TEA (1.33 g, 13.16mmol) was added dropwise at −78° C. The mixture was gradually warmed toRT, and stirred for 2 h. The mixture was concentrated at low pressure,and the residue was dissolved in methyl-butyl ether. The precipitate wasfiltered off, and the filtrate was concentrated at low pressure. Theresidue was purified by a silica gel column (pure AcOEt) to give 233-1as colorless oil (500 mg, 20%).

To a solution of 233-2 (300 mg, 0.337 mmol) and NMI (276.6 mg, 3.37mmol) in anhydrous CH₃CN (0.9 mL) was added 233-1 (388 mg, 1.011 mmol)in CH₃CN (0.3 mL) dropwise at 0° C. The mixture was stirred at RTovernight. The reaction was quenched with water, and extracted withAcOEt. The organic phase was washed with brine, dried over anhydroussodium sulfate, and concentrated at low pressure. The residue waspurified by silica gel column (33% EA in PE) to give 233-3 as a yellowpowder (300 mg, 71.9%).

233-3 (300 mg, 0.243 mmol) was dissolved in 80% CH₃COOH (3 mL), and themixture was stirred at 60° C. for 2.5 h. The mixture was partitionedbetween AcOEt and water. The organic layer phase was washed by brine,dried over sodium sulfate and concentrated at low pressure. The residuewas purified by silica gel column (50% EA in PE) to give 233 as a yellowpowder (81 mg, crude product). The crude product (81 mg) was purified byRP HPLC to give 233 as a white solid. (28.7 mg, 17.1%). ESI-LCMS: m/z694.1 [M+H]⁺.

Example 131 Compound 234

234-1 was prepared using a similar procedure as for the preparation of233-1 using phosphoryl trichloride (2.00 g, 13.16 mmol), 1-naphthol(1.882 g, 13.16 mmol) and (S)-neopentyl 2-aminopropanoate hydrochloride(2.549 g, 13.16 mmol). 234-1 (600 mg, 12%) was obtained as a colorlessoil.

A solution of 234-2 (230 mg 0.26 mmol) and NMI (212 mg 2.60 mmol) inanhydrous CH₃CN (1 mL) was treated with a solution of 234-1 (300 mg 0.78mmol) in anhydrous CH₃CN (0.5 mL) at RT. The mixture was stirred at RTovernight. The reaction was quenched with water, and extracted with EA(3×20 mL). The organic layer was washed with brine, dried by anhydroussodium sulfate, and concentrated at low pressure. The residue waspurified by a silica gel column (CH₃OH in CH₂Cl₂ from 1% to 5%) to give234-3 (300 mg, 93%) as a white solid.

234-3 (300 mg, 0.24 mmol) was dissolved in CH₃COOH (80%, 5 mL). Themixture was stirred at 60° C. for 2.5 h. The mixture was diluted with EA(30 mL) and washed with brine. The organic phase was dried overanhydrous sodium sulfate, and concentrated at low pressure. The residuewas purified by a silica gel column (CH₃OH in CH₂Cl₂ from 1% to 5%) togive crude 234 (105 mg). The crude product was purified by HPLC (0.1%NH₄HCO₃ in water and CH₃CN) to give 234 (45 mg, 26%) as a white solid.ESI-LCMS: m/z 693.2 [M+H]⁺.

Example 132 Compound 235

A stirred solution of 235-1 (2.00 g, 13.99 mmol) and 235-2 (2.00 g,13.99 mmol) in anhydrous DCM (8 mL) was treated with a solution of TEA(3.11 g, 30.8 mmol) in DCM (20 mL) dropwise at −78° C. The mixture wasstirred for 2 h. at −78° C. and then gradually warmed to RT. The organicsolvent was removed at low pressure, and the residue was dissolved inmethyl-butyl ether. The precipitate was filtered off, and the filtratewas concentrated at low pressure. The residue was purified on a silicagel column (dry DCM) to give 235-3 as colorless oil (1 g, 20.96%).

235-4 (260 mg, 0.29 mmol) was coevaporated with toluene 3 times toremove H₂O. Dried 235-4 was treated with MeCN (0.8 mL) and NMI (240 mg,2.9 mmol) and then stirred for 10 mins. The mixture was treated with asolution of 235-3 (291 mg, 0.87 mmol) in MeCN (0.4 mL), and thenconcentrated at low pressure. The residue was purified on a silica gelcolumn (75% EA in PE)) to give 235-5 (300 mg, 86%) as a white solid.

235-5 (300 mg, 0.25 mmol) was treated with CH₃COOH (5 mL, 80%), andstirred at 50° C. for 3 h. The mixture was diluted with EA. The solutionwas washed with brine, dried over anhydrous Na₂SO₄, and concentrated atlow pressure. The residue was purified by silica gel columnchromatography (67% EA in PE) to give crude 235, which was purified byHPLC. The product was dried by lyophilization to give 235 (30 mg, 18.5%)as a white solid. ESI-LCMS: m/z 643 [M+H]⁺.

Example 133 Compound 247

247-1 (50 mg, 0.13 mmol) was dissolved in 80% formic acid (3 mL) andheated at 50° C. overnight. The solvent was evaporated, co-evaporatedwith water to remove the acid. The residue was dissolved in a mixture ofmethanol and triethylamine (3 mL, 4:1 v:v). After 0.5 h, the solvent wasevaporated. The nucleoside was lyophilized from water to yield 247 (40mg, 97%). MS: m/z 315.5 [M−1].

Example 134 Compound 248

To a stirred solution of 248-1 (15.0 g, 50.2 mmol) in anhydrous pyridine(180 mL) was added BzCl (23.3 g, 165.5 mmol) at 0° C. under N₂atmosphere. The mixture was stirred for 12 h at RT. The mixture wasdiluted with EA and washed with sat. NaHCO₃ aq. solution and brine. Theorganic layer was dried with anhydrous Na₂SO₄ and filtered. The organicphase was concentrated to dryness at low pressure. The residue waspurified by column chromatography (15% EtOAc in PE) to give 248-2 (27 g,93.5%) as a white solid.

248-2 (27.0 g, 47 mmol) was dissolved in 90% HOAc (250 mL). The mixturewas stirred at 110° C. for 12 h. The solvent was removed under reducedpressure. The residue was diluted with EA and washed with sat. NaHCO₃aq. solution and brine. The organic layer was dried over anhydrousNa₂SO₄ and filtered. The organic phase was concentrated at low pressureto give crude 248-3 (21.7 g, crude) as a light yellow solid.

248-3 (21.7 g, 45.9 mmol) was treated with NH₃/MeOH (600 mL) and stirredat RT for 12 h. The solvent was concentrated under reduced pressure togive the crude product. The crude product was purified by columnchromatography (5% MeOH in DCM) to give 248-4 (12 g, 99%) as a whitesolid.

To a stirred solution of 248-4 (15.0 g, 56.8 mmol) in anhydrous pyridine(200 mL) was added imidazole (7.7 g, 113.6 mmol) and TBSCl (9.4 g, 62.5mmol) at RT. The mixture was stirred at RT for 12 h. The solvent wasremoved under reduced pressure. The residue was diluted with EA andwashed with sat. NaHCO₃ aq. solution and brine. The organic phase wasdried over anhydrous Na₂SO₄ and filtered. The organic phase wasconcentrated at a low pressure to give crude 248-5 (21.3 g, crude) as alight yellow solid.

To a stirred solution of 248-5 (21.3 g, crude) in anhydrous DCM (200 mL)was added collidine (6.8 g, 56.8 mmol), MMTrCl (17.8 g, 56.8 mmol) andAgNO₃ (9.6 g, 56.8 mmol) at RT. The mixture was stirred at RT for 12 h.The solid was removed by filtration, and the filtrate was washed withsat. NaHCO₃ aq. solution and brine. The organic layer was dried overanhydrous Na₂SO₄ and concentrated at low pressure. The residue waspurified by column chromatography (5% EA in PE) to give 248-6 (32 g,87%) as a light yellow solid.

248-6 (32 g, 49.2 mmol) was dissolved in a solution of TBAF in THF (1M,4.0 eq.) at RT. The mixture was stirred at RT for 12 h. The solvent wasremoved under reduced pressure. The residue was diluted with EA andwashed with brine. The organic layer was dried over anhydrous Na₂SO₄ andconcentrated at low procedure. The residue was purified by columnchromatography (33% EA in PE) to give 248-7 (21.0 g, 79%) as a whitesolid.

To a stirred solution of 248-7 (21.0 g, 38.8 mmol) in anhydrous DCM (200mL) was added pyridine (9.2 mL, 116.4 mmol) and Dess-Martin periodinane(49 g, 116.4 mmol) at 0° C. The mixture was stirred at RT for 4 h. Thereaction was quenched with sat. Na₂S₂O₃ solution and sat. NaHCO₃ aq.solution. The organic layer was washed with brine, dried over anhydrousNa₂SO₄ and concentrated under reduced pressure to give a crude product(21.0 g).

The crude product (21.0 g, crude) was dissolved in dioxane (200 mL) andtreated with 37% aqueous formaldehyde (20 mL, 194 mmol) and 2.0 Naqueous sodium hydroxide (37.5 mL, 77.6 mmol). The mixture was stirredat RT for 12 h. The solution was treated with NaBH₄ (8.8 g, 232.8 mmol).After stirring for 0.5 h at RT, the reaction was quenched with icewater. The mixture was diluted with EA and washed with brine. Theorganic phase was dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified by column chromatography (4% MeOH inDCM) to give 248-8 (10.0 g, 50.5%) as a white foam.

248-8 (4.8 g, 8.5 mmol) was co-evaporated with toluene (2×). The residuewas dissolved in anhydrous DCM (45 mL) and pyridine (6.7 g, 85 mmol).The solution was cooled to 0° C. Triflic anhydride (4.8 g, 18.7 mmol)was added dropwise over 10 mins. At 0° C., the mixture was stirred over40 mins and monitored by TLC (PE: EA=1:1). The mixture was diluted withCH₂Cl₂ (50 mL). The solution was washed with sat. NaHCO₃ solution. Theorganic phase was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by columnchromatography (PE: EA=100:0-4:1) to give 248-9 (6.1 g, 86.4%) as abrown foam.

248-9 (6.1 g, 7.3 mmol) was dissolved in MeCN (25 mL). A solution ofTBAF in THF (1M, 25 mL) was added at RT. The mixture was stirred at RTfor 12 h. A solution of TBAF in THF (1M, 15 mL) was added, and themixture was stirred for 4 h. The mixture was treated with aq. NaOH (1N,14.6 mmol) and the mixture was stirred for 1 h. The reaction wasquenched with water and extracted with EA. The organic phase was washedwith brine, dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified by column chromatography (50% EA inPE) to give 248-10 (2.1 g, 50.6%) as a white solid.

248-10 (700 mg, 1.23 mmol) was dissolved in 80% HCOOH (40 mL) at RT. Themixture was stirred at RT for 2 h. The reaction was quenched with MeOH(40 mL) and stirred for 12 h. The solvent was concentrated at lowpressure, and the residue was purified by column chromatography (5% MeOHin DCM) to give 248 (210 mg, 57.7%) as a white solid. ESI-MS: m/z 296.9[M+H]⁺.

Example 135 Compound 250

A mixture of 250-1 (120 g, 0.26 mol) and IBX (109 g, 0.39 mol) in CH₃CN(2.0 L) was heated to refluxed and stirred for 12 h. After cooling downto RT, the mixture was filtered. The filtrate was concentrated todryness at low pressure.

250-2 (130 g, crude, 0.26 mol) was co-evaporated with anhydrous toluene(3×). Vinyl magnesium bromide (700 mL, 0.78 mol, 1.0 N in THF) was addeddropwise into a solution of 250-2 in THF (300 mL) over 30 mins at −78°C., and the mixture was stirred for about 1 h at RT. When the startingmaterial was consumed as determined by TLC, the mixture was poured intoa sat. NH₄Cl solution. The organic layer was washed with brine, driedover anhydrous Na₂SO₄, and concentrated at low pressure.

To a solution of the above residue (170 g, crude, 0.346 mol) inanhydrous CH₂Cl₂ was added TEA (105 g, 1.04 mol), DMAP (84 g, 0.69 mol),and benzoyl chloride (146 g, 1.04 mol), and stirred for 12 h at RT. Themixture was diluted with CH₂Cl₂ and washed with sat. aq. NaHCO₃. Thecombined aq. phase was extracted with DCM (100 mL). The combined organicphase was dried over anhydrous Na₂SO₄, filtered and evaporated todryness under reduced pressure. The residue was purified by columnchromatography using EA in PE (10% to 50%) to get 250-3 (107 g, 52%).

A mixture of uracil (co-evaporated with toluene (2×)) and NOBSA (81.4 g,0.4 mol) and CH₃CN (150 mL) was stirred to reflux for 1.5 h. Aftercooling to RT, the mixture was treated with 250-3 (59 g, 0.1 mol) andTMSOTf (155 g, 0.7 mol). The mixture was heated to 60-70° C., andstirred for 12 h. After cooling to RT, the mixture was poured into asat. NaHCO₃ solution, and a solid precipitated. After filtration, pure250-4 was obtained as a white solid (40 g, 69%) was obtained.

To a solution of 250-4 (50 g, 0.086 mol), K₂CO₃ (17.8 g, 0.13 mol) inDMF (50 mL) was added PMBCl (16 g, 0.1 mol) at 0° C., and stirred at RTfor 12 h. The reaction was quenched with water, and extracted with EA(3×100 mL). The organic phase was washed with brine, dried overanhydrous Na₂SO₄, and concentrated at low pressure to give 250-5 (65 g).

A mixture of 250-5 (65 g, 0.086 mol) and NaOMe (16.8 g, 0.3 mol) inMeOH:DCM (500 mL, v:v=4:1) was stirred at RT for 2.5 h. The reaction wasquenched with CO₂ (solid) and concentrated at low pressure. The residuewas dissolved in EA (200 mL). The solution was washed with water, driedover anhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by column chromatography (4% MeOH in DCM) to give 250-6 as ayellow foam (25 g, 75%).

To a mixture of 250-6 (25.5 g, 0.065 mol) in DMF (60 mL) was added NaH(10.5 g, 0.26 mol, 60% in coal oil) BnBr (36.3 g, 0.21 mol) in an icebath, and stirred at RT for 12 h. The reaction was quenched with NH₄Cl(aq.), and the mixture was diluted with EA (150 mL). The solution waswashed with brine, dried over anhydride Na₂SO₄, and concentrated at lowpressure. The residue was purified by sil-gel (15% EA in PE) to give250-7 (20 g, 46%).

To a solution of 250-7 (20 g, 0.03 mol) and NMMO (7 g, 0.06 mol) inTHF:H₂O (100 mL, v:v=5:1) was added OsO₄ (2.6 g, 0.01 mol) at RT, andstirred at RT for 24 h. The reaction was quenched with sat. Na₂S₂O₃solution, and extracted with EA (3×80 mL). The organic layer was washedwith brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure.

To a solution of diol-product (0.03 mol) in MeOH:H₂O:THF (v:v:v=170mL:30 mL:50 mL) was added NaIO₄ (9.6 g, 0.045 mol) at RT, and stirred atRT for 2 h. After filtration, the filter was used directly for the nextstep.

The previous solution was treated with NaBH₄ (1.8 g, 0.048 mol) at 0°C., and stirred at RT for 30 mins. The reaction was quenched with HCl (1N) solution. The mixture was extracted with EA (3×60 mL). The organicphase was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by sil-gel (25%EA in PE, TLC: PE:EA=2:1, Rf=0.6) to give 250-8 (12 g, 61% over 3steps).

To a solution of 250-8 (14 g, 21 mmol) and DMAP (5.1 g, 42 mmol) in DCM(60 mL) was added MsCl (3.1 g, 27 mmol) at 0° C., and stirred at RT for40 mins. The reaction was quenched with sat. NaHCO₃ solution. Theorganic phase was washed with HCl (0.2 N) solution, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bysil-gel (25% EA in PE) to give the Ms-product (14 g, 90%) as a whitesolid.

Ms-product (41 g, 55 mmol) was treated with TBAF (Alfa, 1 N in THF, 500mL), and stirred at 70-80° C. for 3 days. The mixture was concentratedat low pressure. The residue was dissolved in EA (200 mL). The solutionwas washed with brine, dried over anhydrous Na₂SO₄, and concentrated atlow pressure. The residue was purified by sil-gel column (25% EA in PE)to give 250-9 (9.9 g, 27%).

To a solution of 250-9 (6.3 g, 9.45 mmol) in CAN:H₂O (v:v=3:1, 52 mL)was added CAN (15.5 g, 28.3 mmol), and stirred at RT overnight. Thereaction was quenched with water, and extracted with EA (3×80 mL). Theorganic phase was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by columnchromatography (25% EA in PE) to give 250-10 (3.6 g, 71%) as a yellowoil.

To a solution of 250-10 (2.4 g, 4.4 mmol) in anhydrous DCM (10 mL) wasadded BCl₃ (1 N, 30 mL) at −70° C., and stirred for 2 h at −70° C. Thereaction was quenched with MeOH at −70° C. The mixture was concentrateddirectly under 35° C. at low pressure. The residue was purified bycolumn chromatography (50% EA in PE to 100% EA) to give 250-11 (1.2 g,86%). ESI-MS: m/z 277.1 [M+H]⁺.

To a solution of PPh₃ (3.37 g, 12.8 mmol) in pyridine (15 mL) was addedI₂ (3.06 g, 12 mmol) at 0° C., and stirred at RT for 30 mins until theorange color appeared. The mixture was cooled to 0° C., and treated with250-11 (2.2 g, 8 mmol) in pyridine (5 mL), and stirred at RT under N₂for 12 h. The reaction was quenched with Na₂S₂O₃ (sat., 30 mL), andextracted with EA (3×60 mL). The organic phase was washed with brine,dried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified by column chromatography (1% to 2% MeOH in DCM) togive 250-12 (1.8 g, 58%) as a light yellow foam.

A mixture of 250-12 (1.35 g, 3.5 mmol) and DBU (1.06 g, 7 mmol) inTHF:CH₃CN (v:v=10 mE:5 mL) was stirred at 60-70° C. for 2 h. The mixturewas diluted with EA (50 mL), and adjusted to pH=7-8 with HCl (0.2 N)solution. The organic phase was washed with brine, dried over anhydrousNa₂SO₄, and concentrated at low pressure. The residue was purified bycolumn chromatography to give 250-13 (0.5 g, 55%).

To a solution of 250-13 (670 mg, 2.6 mmol) in CH₃CN (6 mL) was added NIS(730 mg, 3.25 mmol) and 3HF.TEA (335 mg, 2.1 mmol) at 0° C., and stirredat RT for 2 h. The reaction was quenched with NaHCO₃ (sat.) solution andNa₂S₂O₃ (sat.) solution, and extracted with EA (3×30 mL). The organicphase was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by columnchromatography (50% EA in PE and 2% MeOH in DCM) to give 250-14 (1.2 g,80%) as a brown oil.

To a solution of 250-14 (1.0 g, 2.47 mmol), DMAP (0.75 g, 6.2 mmol) andTEA (0.75 g, 7.42 mmol) in DCM (10 mL) was added BzCl (1.15 g, 8.16mmol) in DCM (1 mL) at 0° C., and stirred at RT for 12 h. The reactionwas quenched with NaHCO₃ (aq.) solution. The organic phase was washedwith brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by column chromatography (30% EA inPE) to give 250-15 (850 mg, 85%).

A mixture of 250-15 (600 mg, 1 mmol), BzONa (1.45 g, 10 mmol), and15-crown-5 (2.2 g, 10 mmol) in DMF (25 mL) was stirred at 90-100° C. for24 h. The mixture was diluted with EA (20 mL). The solution was washedwith brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by column chromatography (30% EA inPE) to give 250-16 (275 mg, 37%) as a light yellow foam.

A mixture of 250-16 (250 mg, 0.41 mmol) in NH₃ MeOH (7 N, 5 mL) wasstirred at RT for 15 h. The mixture was concentrated at low pressuredirectly. The residue was purified by column chromatography (50% EA inPE) and re-purified by prep-HPLC to give 250 (33 mg, 25%) as a whitesolid. ESI-MS: m/z 295.1 [M+H]⁺.

Example 136 Compound 126

To a solution of 126-1 (3.0 g, 11.15 mmol) in anhydrous pyridine (90 mL)was added imidazole (3.03 g, 44.59 mmol) and TBSCl (6.69 g, 44.59 mmol)at 25° C. under N₂ atmosphere. The solution was stirred at 25° C. for 15h. The solution was concentrated to dryness under reduced pressure. Theresidue was dissolved in EA. The solution was washed with sat. NaHCO₃and brine, and dried over anhydrous MgSO₄. The solvent was removed atlow pressure to give crude 126-2 (4.49 g, 90%) as a white solid.

To a stirred solution of 126-2 (3.5 g, 7.04 mmol) in a mixture of EA andEtOH (1:1, 55 mL) was added TsOH (10.7 g, 56.34 mmol) at 0° C. Themixture was stirred at 30° C. for 8 h. Water (30 mL) was added, and thesolution was removed to dryness. The residue was purified on a silicagel column (10% MeOH in DCM) to give 126-3 (1.75 g, 65%) as a whitefoam.

To a solution of 126-3 (3.4 g, 8.88 mmol) in anhydrous pyridine (17 mL)was added collidine (4.3 g, 35.51 mmol), AgNO₃ (5.50 g, 35.51 mmol) andMMTrCl (8.02 g, 26.63 mmol) at 25° C. under N₂. The mixture was stirredat 25° C. for 12 h. MeOH (20 mL) was added, and the solvent was removedto dryness at low pressure. The residue was purified on a silica gelcolumn (10% EA in PE) to give 126-4 (5.76 g, 70%) as a white foam.

To a solution of 126-4 (2.0 g, 2.16 mmol) in anhydrous DCM (10 mL) wasadded Cl₂CHCOOH (2.8 g, 21.57 mmol) dropwise at −78° C. The mixture waswarmed to −10° C. and stirred at this temperature for 20 mins. Thereaction was quenched with sat. NaHCO₃ at −10° C. The mixture wasextracted with DCM, washed with brine, and dried over anhydrous MgSO₄.The solution was concentrated at low pressure. The residue was purifiedon silica gel column (10% EA in PE) to give 126-5 (0.99 g, 70%) as awhite foam.

To a stirred solution of 126-5 (3.5 g, 5.34 mmol) in anhydrous DMSO (35mL) was added DCC (3.30 g, 16.03 mmol) and Py.TFA (1.03 g, 5.34 mmol).The mixture was stirred at 30° C. for 1 h. The reaction was quenchedwith cold water at 0° C., and extracted with EA (3×60 mL). Theprecipitate was filtered. The organic layers were washed with brine (3×)and dried over anhydrous MgSO₄. The organic phase was concentrated atlow pressure to give crude 126-6 (3.5 g) as a yellow oil.

To a stirred solution of 126-6 (3.5 g, 5.34 mmol) in MeCN (35 mL) wasadded 37% HCHO (11.1 mL) and TEA (4.33 g, 42.7 mmol). The mixture wasstirred at 25° C. for 12 h. The mixture was treated with EtOH (26 mL)and NaBH₄ (3.25 g, 85.5 mmol) and then stirred for 30 mins. The reactionwas quenched with sat. aq. NH₄Cl and extracted with EA (3×60 mL). Theorganic layer was dried over anhydrous MgSO₄, and concentrated at lowpressure. The residue was purified by column chromatography (from 10% EAin PE to 50% DCM in PE) to give 126-7 (1.46 g, 40%) as a white solid.

To a stirred solution of 126-7 (1.85 g, 2.7 mmol) in pyridine (24 mL)and DCM (9.6 mL) was added DMTrCl (1.3 g, 3.9 mmol) at −35° C. under N₂atmosphere. The solution was stirred at 25° C. for 16 h. The mixture wastreated with MeOH (15 mL) and concentrated at low pressure. The residuewas purified by column chromatography (EA in PE from 10% to 30%) to give126-8 (1.60 g, 60%) as a white solid.

To a solution of 126-8 (1.07 g, 1.08 mmol) in anhydrous pyridine (5 mL)was added AgNO₃ (0.65 g, 3.79 mmol) and TBDPSCl (1.04 g, 3.79 mmol). Themixture was stirred at 25° C. for 16 h. The solvent was removed underreduced pressure. The residue was dissolved in EA (50 mL). The resultingsolution was washed with brine. The organic layer was dried overanhydrous MgSO₄, and concentrated at low pressure. The residue waspurified on a silica gel column (10% EA in PE) to give 126-9 (0.93 g,70%) as a white foam.

To a stirred solution of 126-9 (1 g, 0.82 mmol) in anhydrous DCM (13.43mL) was added Cl₂CHCOOH (2.69 mL) at −78° C. The mixture was stirred at−10° C. for 20 mins. The reaction was quenched with sat. aq. NaHCO₃ andextracted with DCM. The organic layer was dried over anhydrous Na₂SO₄,and concentrated at low pressure. The organic phase was purified bycolumn chromatography (MeOH in DCM form 0.5% to 2%) to give 126-10 (0.48g, 65%) as a solid.

To an ice cold solution of 126-10 (0.4 g, 0.433 mmol) in anhydrous DCM(2.7 mL) was added pyridine (171 mg, 2.17 mmol) and Tf₂O (183 mg, 0.65mmol) by dropwise at −35° C. The mixture was stirred at −10° C. for 20mins. The reaction was quenched with ice water and stirred for 30 mins.The mixture was extracted with DCM (3×20 mL). The organic phase waswashed with brine (100 mL), dried over anhydrous Na₂SO₄, andconcentrated at low pressure to give crude 126-11 (0.46 g), which wasused for next step without further purification.

To a solution of 126-11 (0.46 g, 0.43 mmol) in anhydrous DMF (2.5 mL)was added NaN₃ (42 mg, 0.65 mmol). The mixture was stirred at 30° C. for16 h. The solution was diluted with water and extracted with EA (3×30mL). The combined organic layers were dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified on a silica gelcolumn (EA in PE from 5% to 15%) to give 126-12 (0.31 g, 70%) as asolid.

To a solution of 126-12 (0.31 g, 0.33 mmol) in MeOH (5 mL) was addedNH₄F (0.36 g, 9.81 mmol) at 70° C. The mixture was stirred at thistemperature for 24 h. The mixture was evaporated to dryness. The residuewas purified on silica gel column (MeOH in DCM from 0.5% to 2.5%) togive 126-13 (117 mg, 60%) as a white solid.

126-13 (300 mg, 0.50 mmol) was dissolved in 80% of HOAc (20 mL). Themixture was stirred at 55° C. for 1 h. The reaction was quenched withMeOH and concentrated at low pressure. The residue was purified byprep-HPLC to give 126 (100 mg, 61.3%) as a white solid. ESI-LCMS: m/z325.1 [M+H]⁺.

Example 137 Compound 137

To a stirred solution of 146-1 (80 mg, 0.14 mmol) in anhydrous CH₃CN(2.0 mL) was added N-methylimidazole (0.092 mL, 1.12 mmol) at 0° C.(ice/water bath). A solution ofphenyl(isopropoxy-L-alaninyl)phosphorochloridate (128 mg, 0.42 mmol,dissolved in CH₃CN (0.5 mL)) was then added (prepared according to ageneral procedure as described in McGuigan et al., J. Med. Chem. (2008)51:5807-5812). The solution was stirred at 0 to 5° C. for h and thenstirred at RT for 16 h. The mixture was cooled to 0 to 5° C., dilutedwith EA followed by the addition of water (5 mL). The solution waswashed with 1.0M citric acid, sat. aq. NaHCO₃ and brine, and dried withMgSO₄. The residue was purified on silica (10 g column) with EA/hexanes(25-100% gradient) to give 137-1 (57.3 mg, 49%) as a foam.

137-1 (57.3 mg, 0.07 mmol) was dissolved in anhydrous CH₃CN (0.5 mL),and 4N HCl in dioxane (68 μL, 0.27 mmol) was added at 0 to 5° C. Themixture was stirred at RT for 2 h, and anhydrous EtOH (100 μL) wasadded. The solvents were evaporated at RT and co-evaporated with toluene(3×). The residue was purified on silica (10 g column) with MeOH/CH₂Cl₂(1-7% gradient) and lypholized to give 137 (27.8 mg, 72%) as a whitefoam. ESI-LCMS: m/z=571.1 [M+H]⁺, 1141.2 [2M+H]⁺.

Example 138 Compound 138

138-1 (68.4 mg, 44.7%) was prepared from 146-1 (100 mg, 0.174 mmol) andbis(tert-butoxycarbonyloxymethyl)phosphate (126 mg, 0.35 mmol) withDIPEA (192 L, 1.04 mmol), BOP-Cl (133 mg, 0.52 mmol), and3-nitro-1,2,4-triazole (59 mg, 0.52 mmol) in THF (1.5 mL) in the samemanner as 169-4.

138 (31.4 mg, 67%) was prepared from 138-1 (68 mg, 0.077 mmol) in thesame manner as 146. ESI-LCMS: m/z=627.15 [M+Na]⁺, 1219.25 [2M+H]⁺.

Example 139 Compound 139

To a solution of 146-1 (100 mg, 0.175 mmol) in anhydrous CH₃CN (2 mL)was added 5-ethylthio-1H-tetrazole in CH₃CN (0.25M; 0.84 mL, 0.21 mmol).Bis-SATE-phosphoroamidate (95 mg, 0.21 mmol) in CH₃CN (1 mL) was addedat 0 to 5° C. dropwise. The mixture was stirred 2 h at 0 to 5° C. underAr. A solution of 77% m-CPBA (78 mg, 0.35 mmol) in DCM (1 mL) was added,and the mixture stirred 2 h at 0 to 5° C. under Ar. The mixture wasdiluted with EtOAc (50 mL), washed with 1.0M citric acid, sat. NaHCO₃and brine, and dried with MgSO₄. The mixture was filtered, and thesolvents were evaporated in vacuo. The residue was purified on silica(10 g column) with EA/hexanes (20-100% gradient) to give 139-1 (105 mg,63.6%) as a white foam.

139-1 (105 mg, 0.112 mmol) was dissolved in anhydrous CH₃CN (0.8 mL),and 4N HCl in dioxane (84 μL, 0.334 mmol) was added at 0 to 5° C. Themixture was stirred at RT for 2 h. Anhydrous EtOH (100 μL) was added.The solvents were evaporated at RT, and co-evaporated with toluene (3×).The residue was purified on silica (10 g column) with MeOH/CH₂Cl₂ (1-7%gradient) and lypholized to give 139 (42.7 mg, 57%) as a white foam,ESI-LCMS: m/z=692.15 [M+Na]⁺, 1339.30 [2M+H]⁺.

Example 140 Compound 143

To a solution of N-Boc-L-Valine (620.78 mg, 2.86 mmol) and TEA (144.57mg, 1.43 mmol) in anhydrous THF (2.5 mL) was added BB (250.00 mg, 285.73μmol). The mixture was co-evaporated with pyridine and toluene to removewater. The residue was dissolved in THF (2.5 mL). DIPEA (369.28 mg, 2.86mmol) was added, followed by addition of BOP-Cl (363.68 mg, 1.43 mmol)and 3-nitro-1H-1,2,4-triazole (162.95 mg, 1.43 mmol) at RT (18° C.). Themixture was stirred at RT for 12 h and then diluted with EA (40 mL). Thesolution was washed with brine, dried over anhydrous Na₂SO₄ andconcentrated to dryness at low pressure. The residue was purified on asilica gel column (30% EA in PE) to give 143-1 (220 mg, crude) as awhite foam.

143-1 (250.0 mg, 232.73 μmol) was dissolved in 80% CH₃COOH (30 mL). Thesolution was heated to 50° C. and stirred for 12 h. The reaction wasquenched with MeOH, and the solution was concentrated to dryness. Theresidue was purified on a silica gel column (5% MeOH in DCM) to give143-2 (80.00 mg, 68.82%) as a white foam.

143-2 (78.00 mg, 156.16 μmol) was dissolved in Hcl/dioxane (1.5 mL) andEA (1.5 mL) at RT (19° C.). The mixture was stirred at RT for 30 mins.The solution was concentrated to dryness at low pressure. The residuewas purified by prep-HPLC to give 143 (23 mg, 31.25%) as a white solid.ESI-MS: m/z 400.20 [M+H]⁺, 799.36 [2M+H]⁺.

Example 141 Compound 154

154-1 was prepared according to the procedure described in Lefebre etal., J. Med. Chem. (1995) 38:3941-3950, which is hereby incorporated byreference for the limited purpose of its description of the preparationof 154-1.

154-2 (0.33 g, 0.5 mmol) was prepared using a similar procedure to theone used to prepare 155-6 using 155-5 and 154-1. 154-2 was obtained as awhite solid. Using a similar procedure to the one used to prepare 155,154-2 was used to prepare 154 (130 mg). ¹H-NMR (CDCl₃): 7.40 (d, 1H),6.1 (s, 1H), 5.83 (d, 1H), 4.3 (t, 2H), 4.1-4.2 (m, 6H), 3.2 (t, 4H),1.69 (s, 4H), 1.3 (s, 3H), 1.23 (s, 18H); ³¹P-NMR (CDCl₃): −2.4 ppm.

Example 142 Compound 155

To a solution of sodium hydrosulfide (4.26 g, 76.0 mmol) in EtOH (100mL) was added t-butyryl chloride (76.2 mmol; 9.35 mL) dropwise at 0° C.,and the mixture was stirred at RT for 1 h. A solution of2-(2-chloroethoxyl)ethanol (57 mmol; 6.0 mL) and TEA (21 mL, 120 mmol)was added, and the mixture was heated at reflux for 60 h. The mixturewas filtered, and then concentrated to a small volume. The residue wasdissolved in EA, and then washed with water, sat. aq. NaHCO₃ and brine.The organic phase was dried over Na₂SO₄, filtered and concentrated invacuo. The crude product (10.0 g) was isolated and 5 grams were purifiedby silica gel flash column chromatography using a gradient of 0 to 100%EA in hexane to give 155-3 (4.5 g, 22 mmol) as a clear, colorless oil.¹H-NMR (CDCl₃): 3.70-3.74 (m, 2H), 3.5-3.65 (m, 4H), 3.1 (t, 2H), 1.25(s, 9H).

A solution 155-3 (4.5 g; 21.8 mmol) and triethylamine (6.7 mL, 87.2mmol) in tetrahydrofuran (50 mL) was added dropwise over 1 h to astirred solution of N,N-diisopropylphosphorodichloridite (2.0 mL, 10.9mmol) in THF (50 mL) under argon at −78° C. The mixture was stirred atRT for 2 h, and then diluted with EA (200 mL). The mixture was washedwith sat. aq. NaCl and dried over Na₂SO₄. After filtration, the filtratewas evaporated under reduced pressure to give a pale yellow oil.Purification by flash column chromatography using a gradient of EA(0-5%) in hexane containing 5% triethylamine afforded 155-4 (2.5 g, 4.25mmol) as a clear, colorless oil. ¹H-NMR (CDCl₃): 3.70-3.82 (m, 4H),3.57-3.65 (m, 10H), 3.1 (t, 4H), 1.25 (s, 18H), 1.17 (t, 12H); ³¹P-NMR(CDCl₃): 148.0 ppm.

155-5 (285 mg, 0.9 mmol) and DCI (175 mg, 1.5 mmol) were coevaporatedtwice with ACN and then dissolved in ACN (5 mL). 155-4 (790 mg, 1.35mmol) in ACN (4 mL) was added, and the reaction was monitored by TLC.After 15 mins, tert-butylhydroperoxide (0.5 mL of 5.5M solution indecane) was added, and the mixture was stirred for 10 mins. The mixturewas diluted with EA (25 mL), washed with sat. aq. NaHCO₃ and sat. aq.NaCl solution, dried over Na₂SO₄, filtered and concentrated.Purification by flash column chromatography using a gradient of EA(0-100%) in hexane afforded 155-6 (0.17 g, 0.22 mmol) as a white solid.155-6 was dissolved in 80% aq. HCOOH (5 mL). After 30 mins at RT, thesolvent was removed and coevaporated twice with toluene. The residue wasdissolved in methanol (10 mL) and TEA (0.2 mL) was added. After 2 minsat RT, the solvent was removed in vacuo. Purification by flash columnchromatography using a gradient of methanol (0-15%) in DCM afforded 155(90 mg). ¹H-NMR (CDCl₃): 7.40 (d, 1H), 6.1 (s, 1H), 5.83 (d, 1H), 4.3(t, 2H), 4.1-4.2 (m, 6H), 3.70-3.82 (m, 4H), 3.57-3.65 (m, 4H), 3.1 (t,4H) 1.61 (s, 8H), 1.3 (s, 3H), 1.23 (s, 18H). ³¹P-NMR (CDCl₃): −1.55ppm.

Example 143 Compound 156

156-1 (6.0 g, 31.6 mmol) was prepared using a similar procedure to theone used to prepare 155-3 using 4-chlorobutanol. 156-1 was obtained as aclear, colorless oil. ¹H-NMR (CDCl₃): 3.67 (s, 2H), 2.86 (m, 2H), 1.65(m, 4H), 1.25 (s, 9H).

156-2 (2.14 g, 4.0 mmol) was prepared using a similar procedure to theone used to prepare 155-4. 156-2 was obtained as a clear, colorless oil.¹H-NMR (CDCl₃): 3.67 (m, 6H), 2.86 (t, 4H), 1.65 (m, 8H), 1.25 (s, 18H),1.17 (t, 12H). ³¹P-NMR (CDCl₃): 143.7 ppm.

156-3 (0.23 g, 0.22 mmol) was prepared using a similar procedure to theone used to prepare 155-6 using 155-5 and 156-2. 156-3 was obtained as awhite solid. Using a similar procedure to the one used to prepare 155,156-3 was used to prepare 156 (170 mg). ¹H-NMR (CDCl₃): 7.40 (d, 1H),6.1 (s, 1H), 5.83 (d, 1H), 4.3 (t, 2H), 4.1-4.2 (m, 6H), 2.8 (t, 4H),1.78 (m, 4H), 1.69 (s, 8H), 1.3 (s, 3H), 1.23 (s, 18H). ³¹P-NMR (CDCl₃):−1.56 ppm.

Example 144 Compound 161

161-1 (109 mg, 0.39 mmol) and triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (0.6 mmol, prepared from 195mg of bis(isopropyloxycarbonyloxymethyl)phosphate and 85 μL of Et₃N)were rendered anhydrous by coevaporating with pyridine, followed bytoluene. The residue was dissolved in anhydrous THF (3 mL) and cooled inan ice-bath. Diisopropylethyl amine (0.2 mL, 3 eq.), BopCl (190 mg, 2eq.), and 3-nitro-1,2,4-triazole (81 mg, 2 eq.) were added, and themixture was stirred at 0° C. for 90 mins. The mixture was diluted withEtOAc, washed with sat. aq. NaHCO₃ and brine, and dried (Na₂SO₄).Purification on silica gel column with CH₂Cl₂/i-PrOH (4-10% gradient)followed by RP-HPLC purification (A: 0.1% HCOOH in water, B: 0.1% HCOOHin MeCN) yielded 161 (28 mg, 12%). ¹H-NMR (CDCl₃): δ 7.24 (d, 1H), 6.6(br, 1H), 5.84 (d, 1H), 5.65-5.73 (m, 4H), 4.94 (m, 2H), 4.38 (m, 2H),4.1 (b, 1H), 2.88 (d, 1H), 1.47 (d, 3H), 1.33 (m, 12H).

Example 145 Compound 266

To an ice cold solution of 270 (50 mg, 0.16 mmol) and N-methylimidazole(50 μL, 0.64 mmol) in acetonitrile (1.5 mL) was added a solution of266-1 (0.1 g, 0.28 mmol) in acetonitrile (0.15 mL). The mixture stirredat 5° C. for 1 h. The reaction was quenched with EtOH, and the mixtureconcentrated. The evaporated residue was partitioned between EtOAc andcitric acid (0.5 N). The organic layer was washed with sat. aq. NaHCO₃and brine, and then dried with Na₂SO₄. Purification by RP-HPLC (A:water, B: MeCN) yielded 266 (30 mg, 30%) as a white powder. MS: m/z 625[M+1].

Example 146 Compound 157

Compound 157-1 was prepared from commercially available 3-hydroxyoxetane(5.0 g) using the procedure described for preparing 54-2 (5.6 g). ¹H-NMR(CDCl₃) δ 5.73 (s, 2H), 5.48-5.51 (m, 1H), 4.90 (d, 2H), 4.72 (d, 2H).

Compound 157-2 was prepared from 157-1 using the procedure described forpreparing 54-3 (8.0 g). ¹H-NMR (CDCl₃) δ 5.95 (s, 2H), 5.48-5.51 (m,1H), 4.90 (d, 2H), 4.72 (d, 2H).

Benzylphosphate (silver salt) and 157-2 (8.0 g) were reacted asdescribed for preparing 54-4 to yield purified 157-3 (1.92 g). ¹H-NMR(CD₃CN): δ 7.39-7.42 (m, 5H), 5.62 (d, 4H), 5.39-5.42 (m, 2H), 5.15 (d,2H), 4.80-4.83 (m, 4H), 4.56-4.60 (m, 4H). ³¹P-NMR (CD₃CN): δ −4.55 ppm.

Compound 157-3 (970 mg, 2.16 mmol) was dissolved in methanol containingtriethylamine (0.3 mL, 2.16 mmol). After 3 h at R.T, the solvents wereremoved in vacuo to give crude 157-4 that was used without furtherpurification.

Compound 157-5 (400 mg; 1.2 mmol) and 157-4 (900 mg, 2.16 mmol; 1.5×)were coevaporated with pyridine (2×) and toluene (2×), and thendissolved in THF (8 mL) at 0° C. Diisopropylethylamine (DIPEA) (0.82 mL;4 eq.), bis(2-oxo-3-oxazolidinyl)phosphinic chloride (Bop-Cl) (0.6 g; 2eq.), nitrotriazole (0.266 g, 2 eq.) were added. The mixture kept at 0°C. for 2 h. The mixture was diluted with EA (50 mL) and extracted withsaturated sodium bicarbonate (2×50 mL) and dried over sodium sulfate.The solvents were removed in vacuo. The residue was purified by flashchromatography using a 10 to 100% gradient of EA in hexane to givepurified 157-6 (175 mg, 0.6 mmol).

Purified 157-6 was dissolved in 80% aq. HCOOH (20 mL) and kept at 20° C.for 1 h. After cooling to RT, the solvent was removed in vacuo, and theresidue coevaporated with toluene (3×25 mL). The residue was purified byflash chromatography using a 0 to 20% gradient of MeOH in DCM to givepurified 157 (26 mg). ESI-LCMS: m/z 589.6 [M−H]⁻.

Example 147 Compound 158

Nucleoside 158-1 (from Wuxi) (44 mg, 0.15 mmol) was dissolved in amixture of trimethyl phosphate (2 mL) and dry pyridine (0.5 mL). Themixture was evaporated in vacuum for 15 mins at 42° C., than cooled toRT. N-Methylimidazole (0.027 mL, 0.33 mmol) was added followed by POCl₃(0.027 mL, 0.3 mmol). The mixture was kept at RT. The reaction wasmonitored by LC/MS in 0-50% gradient. After 4 h, the reaction wascomplete. The reaction was quenched with 2M triethylammonium acetatebuffer (2 mL), pH7.5 (TEAA). 158-2 was isolated on prep-HPLC (PhenomenexSynergi 4u Hydro-RP 250×21.2 mm) using a gradient of 0-30% ACN in 50 mMTEAA.

Compound 158-2 (triethylammonium salt; 45 mg, 0.1 mmol) was dried byrepeated co-evaporation with dry pyridine (3×). 158-2 was dissolved indry pyridine (1 mL) and the solution added dropwise into a boilingsolution of diisopropylcarbodiimide (63 mg, 0.5 mmol) in pyridine (4 mL)over 2.5 h. The mixture was heated under reflux for 1 h. After beingcooled to 25° C., the reaction was quenched with 2M TEAA buffer (2 mL)and kept at 25° C. for 1 h. The solution was concentrated to dryness,and the residual pyridine removed by coevaporated with toluene (3×2 mL).158-3 was isolated on prep-HPLC (Phenomenex Synergi 4u Hydro-RP 250×21.2mm) using a gradient of 0-30% ACN in 50 mM TEAA.

Compound 158-3 (triethylammonium salt; 26 mg, 0.045 mmol) was dissolvedin dry DMF (0.5 mL) at RT under argon. To the stirred solution was addedN,N-diisopropylethylamine (40 uL, 0.22 mmol) followed by chloromethylisopropyl carbonate (35 mg, 0.22 mmol). The mixture was stirred at 65°C. for 18 h. The mixture was evaporated to dryness, and the residue waspurified by silica column using a 0-15% gradient of MeOH in CH₂Cl₂. Thefractions having 158 were pooled, and the mixture was concentrated todryness to give 158 (2.3 mg). ESI-LCMS: m/z 467.5 [M−H]⁻.

Example 148 Compound 267

To a stirred solution of 267-1 (180 mg, 0.16 mmol) in anhydrous CH₃CN(2.0 mL) was added N-methylimidazole (53.4 μL, 0.65 mmol) at 0° C.(ice/water bath). A solution ofphenyl(cyclohexyloxy-L-alaninyl)phosphorochloridate (101 mg, 0.29 mmol)dissolved in CH₃CN (0.5 mL), prepared according to a general procedure(McGuigan et al., J. Med. Chem. (2008) 51:5807-5812), was added. Thesolution was stirred at 0 to 5° C. for 3 h. N-methylimidazole (50 μL) at0° C. (ice/water bath) followed by solution of phenyl(cyclohexyloxy-L-alaninyl)phosphorochloridate (52 mg, dissolved in 0.5mL of CH₃CN) were added. The mixture was stirred at RT for 16 h. Themixture was cooled to 0 to 5° C. and diluted with EA. Water (5 mL) wasadded. The solution was washed with 1.0M citric acid, sat. aq. NaHCO₃and brine, and dried with MgSO₄. The residue was purified on silica (10g column) with DCM/MeOH (0-10% gradient) to give 267-2 (96.8 mg, 64%) asfoam.

Compound 267-2 (95 mg, 0.11 mmol) was dissolved in anhydrous CH₃CN (0.5mL), and 4N HCl in dioxane (77 μL, 0.3 mmol) was added at 0 to 5° C. Themixture was stirred at RT for 30 mins, and anhydrous EtOH (100 μL) wasadded. The solvents were evaporated at RT and co-evaporated with toluene(3×). The residue was purified on RP-HPLC with H₂O/CH₃CN (50-100%gradient) and lypholized to give 267 (37.7 mg, 52.5%) as a white foam.ESI-LCMS: m/z=653.2 [M+H]⁺, 1305.4 [2M+H]⁺.

To a solution of 267-A (56 g, 0.144 mol) in anhydrous THF (600 mL) wasadded a solution of lithium tri-tert-butoxyaluminohydride (216 mL, 1M,0.216 mol) dropwise at −78° C. under N₂ for 30 mins. The solution wasstirred between −78° C. to 0° C. for 1 h. The reaction was quenched withsat. NH₄Cl solution and extracted with EA (3×200 mL). The combinedorganic layers were dried over anhydrous Na₂SO₄, filtrated andconcentrated to give 267-B (52 g, 92%) as a colorless oil.

To a stirred solution of PPh₃ (45.7 g, 0.174 mol) in CH₂Cl₂ (200 mL) wasadded 267-B (34 g, 0.087 mol) at −20° C. under N₂. The mixture wasstirred for 15 mins. CBr₄ (58 g, 0.174 mol) was added dropwise whilemaintaining the temperature between −25° C. and −20° C. under N₂ flow.The mixture was then stirred below −17° C. for 20 mins. The mixture wastreated with silica gel. The solution was filtered through cold silicacolumn gel and washed with cold elute (PE:EA=50:1 to 4:1). The combinedfiltrates were concentrated under reduced pressure at RT to give thecrude oil product. The residue was purified by silica column gel(PE:EA=50:1 to 4:1) to give 267-C (α-isomer, 24 g, 61%) as a colorlessoil. ¹H-NMR (CDCl₃, 400 MHz), δ=8.16 (d, J=6.8 Hz, 2H), 8.01 (d, J=7.6Hz, 2H), 7.42-7.62 (m, 6H), 6.43 (s, 1H), 5.37 (d, J=4.4 Hz, 1H),4.68-4.86 (m, 3H), 1.88 (s, 3H).

A mixture of 6-Cl-guanosine (80.8 g, 0.478 mol) and t-BuOK (57 g, 0.509mol) in t-BuOH (1 L) was stirred at 30-35° C. for 30 mins. 267-C (72 g,0.159 mol, in MeCN 500 mL) was added at RT and the mixture was heated to70° C. and stirred for 3 h. The reaction was quenched with sat. NH₄Clsolution, and extracted with EA (3×300 mL). The combined organic layerswere dried over anhydrous Na₂SO₄ and evaporated at low pressure. Theresidue was purified by silica gel column (PE:EA=4:1 to 2:1) to give267-D (14 g, 16%). ¹H-NMR (CDCl₃, 400 MHz) δ 7.93-8.04 (m, 4H), 7.90 (s,1H), 7.30-7.50 (m, 6H), 6.53 (d, J=8.8 Hz, 1H), 6.36 (s, 1H), 5.35 (s,2H), 5.06-5.10 (m, 1H), 4.81-4.83 (m, 1H), 4.60-4.64 (m, 1H), 1.48 (s,3H).

To a solution of 267-D (14 g, 25.9 mmol) in DCM (15 mL) was added AgNO₃(8.8 g, 51.8 mmol) and collidine (6.3 g, 51.8 mmol) and MMTrCl (12.1 g,38.9 mmol). The mixture was stirred at RT for 1 h. The reaction wasquenched with MeOH (5 mL). After filtration, the filter was washed withbrine, dried over anhydrous Na₂SO₄, and concentrated at low pressure.The residue was purified by silica gel column (PE:EA=10:1 to 3:1) togive 267-E (16 g, 80%). ¹H-NMR (CDCl₃, 400 MHz) δ=8.05-8.07 (m, 4H),7.93 (s, 1H), 7.18-7.57 (m, 18H), 6.77 (d, J=8.8 Hz, 2H), 6.71 (s, 1H),5.86 (s, 1H), 5.6 (s, 1H), 4.77 (d, J=10.0 Hz, 1H), 4.67-4.76 (m, 1H),4.55-4.59 (m, 1H), 3.75 (s, 1H), 1.06 (s, 3H).

Sodium (170 mg, 7.38 mmol) was dissolved in dry EtOH (5 mL) at 70° C.,and the solution was cooled to 0° C. 267-E (1 g, 1.23 mmol) was added inportions at 0° C. The mixture was stirred for 8 h at RT. The mixture wasneutralized with CO₂ to pH 7.0, and concentrated at low pressure. Theresidue was purified by prep-HPLC (10% CH₃CN/H₂O) to give 267-1 (0.4 g,53%) as a yellow solid. ESI-MS: m/z 616 [M+H]⁺.

Example 149 Compound 272

To a stirred solution of 272-1 (3.00 g, 5.23 mmol) in anhydrous DCM (36mL) was added PDC (3.94 g, 10.46 mmol), Ac₂O (5.34 g, 52.30 mmol) and2-methylpropan-2-ol (7.75 g, 104.60 mmol) at RT. The mixture was stirredat RT for 15 h. The mixture was loaded on a very short silica gel columnand eluted with EA. The fractions containing the product were combinedand concentrated under reduced pressure. The residue was purified bycolumn chromatography (20% EA in PE) to give 272-2 (2.40 g, 71.3%) as awhite foam.

To a stirred solution of 272-2 (2.00 g, 3.26 mmol) in DCM (30 mL) wasadded TFA (15 mL). The mixture was stirred at RT for 1.5 h. The mixturewas concentrated under reduced pressure to give 272-3 (1.00 g, crude),which was used in the next step without further purification.

Crude 272-3 (1.00 g, crude) was dissolved in a mixture of toluene (25mL) and MeOH (20 mL). TMS-diazomethane (2 M, 3.17 mL) was added. Afterstirring for 2 h, the mixture was concentrated under reduced pressure atRT. The residue was diluted with EA (25 mL), washed with water (25 mL),dried over anhydrous MgSO₄, filtered and concentrated under reducedpressure. The residue was purified by column chromatography (2% MeOH inDCM) to give 272-4 (451 mg, 43.2%) as a white solid. The aqueous phasewas concentrated to give 272-3 (500 mg, 50.0%) as a white solid.

To a solution of 272-4 (451 mg, 1.37 mmol) in anhydrous CD₃OD (18 mL)was added NaBD₄ (344 mg, 8.22 mmol) at RT. The mixture was stirred at RTfor 1 h. The reaction was quenched with CD₃OD (0.2 mL) and neutralizedwith AcOH (0.2 mL). The mixture was concentrated under reduced pressure.The residue was purified by column chromatography (4% MeOH in DCM) togive 272-5 (410 mg, 98.7%) as a white solid.

To a stirred solution of 272-5 (410 mg, 1.35 mmol) in pyridine (2.5 mL)was added imidazole (459 mg, 6.75 mmol) and TBSCl (610 mg, 4.05 mmol) atRT. The mixture was stirred at 60° C. for 10 h. The mixture wasconcentrated under reduced pressure. The residue was diluted with EA (20mL) and washed with brine (20 mL). The organic layer was dried overMgSO₄ and filtered. The filtrate was concentrated under reducedpressure. The residue was purified by column chromatography (10% EA inPE) to give 272-6 (440 mg, 61.3%) as a white solid.

To a solution of 272-6 (440 mg, 827 μmol) in anhydrous MeCN (4 mL) wereadded DMAP (253 mg, 2.07 mmol), Et₃N (209.32 mg, 2.07 mmol) and2,4,6-triisopropylbenzene-1-sulfonyl chloride (626.50 mg, 2.07 mmol) atRT. The mixture was stirred at RT for 16 h. NH₃.H₂O (2 mL) was added,and the mixture was stirred for 1 h. The mixture was diluted with EA (20mL) and washed with sat. aq. NH₄Cl (20 mL). The organic layer was driedover anhydrous Na₂SO₄ and filtered. The filtrate was concentrated underreduced pressure. The residue was purified by column chromatography (2%MeOH in DCM) to give the crude product. The crude product was purifiedby TLC (10% MeOH in DCM) to give 272-7 (420 mg, 95.63%) as a whitesolid.

To a solution of 272-7 (420 mg, 791 mol) in MeOH (4 mL) was added NH₄F(586 mg, 15.83 mmol) at RT. The mixture was stirred at 90-100° C. for 10h. The mixture was filtered, and the filtrate was concentrated underreduced pressure. The residue was purified by column chromatography (10%MeOH in DCM) to give the crude product. The crude product was purifiedby prep-HPLC (neutral condition) to give 272 (201 mg, 61.8% yield, 100%deuterium) as a white solid. ESI-TOF-MS: m/z 303.1 [M+H]⁺, 605.2[2M+H]⁺.

Example 150 Compound 221

To a solution of 1,1-dimethoxycyclopentane (19.3 g, 148.52 mmol) and221-1 (10.0 g, 37.13 mmol) in DCE (100 mL) was added TsOH.H₂O (0.7 g,3.71 mmol). The mixture was stirred at 50° C. for 12 h. The mixture wasneutralized with Et₃N, and concentrated at low pressure. The residue waspurified by silica gel column chromatography (1-10% MeOH in DCM) to give221-2 (8.7 g, 70.1%) as a white solid.

Compound 221-2 (20.0 g, 0.06 mol) was coevaporated with anhydrouspyridine 3 times to remove H₂O. To an ice-cold solution of 221-2 inanhydrous pyridine (100 mL) was added TsCl (22.8 g, 0.12 mol) at 0° C.,and the mixture was stirred overnight. The reaction was monitored byLCMS and TLC. The reaction was quenched with H₂O, and the mixtureextracted with EA (3×200 mL). The solution was dried over anhydrousNa₂SO₄ and evaporated at low pressure. The residue was purified bysilica gel column chromatography (DCM: MeOH=100:1 to 15:1) to give 221-3(20.0 g, 69.0%) as a white solid.

To a solution of 221-3 (20.0 g, 0.04 mol) in acetone (200 mL) was addedNaI (31.0 g, 0.2 mol), and the mixture was heated to reflux overnight.The reaction was monitored by LCMS. The reaction was quenched with asat. Na₂S₂O₃ solution. The solution was extracted with EA (3×200 mL).The organic layer was dried over anhydrous Na₂SO₄, and evaporated at lowpressure. The residue was purified by silica gel column chromatography(DCM: MeOH=100:1 to 15:1) to give 221-4 (15.0 g, 83.3%) as a whitesolid.

Compound 221-4 (13.4 g, 30.16 mmol) was treated with HCOOH (80%) in H₂Oat RT. The solution was stirred at 60° C. for 2 h. The mixture wasconcentrated at low pressure. The residue was purified by columnchromatography (1%-10% MeOH in DCM) to give 221-5 (9.1 g, 80.0%) as awhite solid.

To a solution of 221-5 (5.0 g, 13.22 mmol) in anhydrous CH₃CN/THF (50mL, 1:1, v:v) was added DBU (6.0 g, 39.66 mmol) at RT. The solution wasstirred at 50° C. for 1.5 h. The reaction was quenched with HCOOH at 0°C., and then concentrated at low pressure. The residue was purified bycolumn chromatography (50%-70% EA in PE) to give 221-6 (3.3 g, 48.1%) asa white solid.

To an ice-cold solution of 221-6 (2.1 g, 8.39 mmol) in anhydrous MeCN(21 mL) was added NIS (2.4 g, 10.49 mmol) and TEA.3HF (1.0 g, 6.29 mmol)under N₂. The mixture was stirred at RT for 1 h. The reaction wasquenched with sat. NaHCO₃ and sat. Na₂SO₃ solution, and extracted withEA (3×100 mL). The organic phase was dried over anhydrous Na₂SO₄, andevaporated to dryness at low pressure. The residue was purified on asilica gel column (30%-50% EA in PE) to give 221-7 (1.3 g, 39.3%) as alight yellow solid.

To a stirred solution of 221-7 (3.2 g, 8.08 mmol) in anhydrous DCM (32mL) was added DMAP (2.5 g, 20.20 mmol) and Et₃N (2.5 g, 24.24 mmol) atRT. The mixture was treated with BzCl (3.7 g, 26.66 mmol) at 0° C. andthen stirred at RT overnight. The reaction was quenched with water, andextracted with EA (3×60 mL). The organic phase was concentrated at lowpressure, and the residue was purified by column chromatography (20%-30%EA in PE) to give 221-8 (1.8 g, 31.6%) as a white solid.

Bu₄NOH (8.0 g, 13.74 mL, 55% in H₂O) was adjusted to pH=3-4 with TFA,and then cooled to RT. To a solution of 221-8 (600 mg, 0.85 mmol) in DCM(10 mL) was added the Bu₄NOH solution and m-CPBA (917 mg, 4.25 mmol,80%) at RT. The mixture was stirred at 25° C. for 48 h and then washedwith a sat. NaHCO₃ solution. The organic layer was directly passedthrough basic Al₂O₃ column, and the solvent was concentrated at lowpressure. The residue was purified by a silica gel column (20%-30% EA inPE) to give 221-9 (123 mg, 24.3%) as a white solid.

To a solution of 221-9 (300 mg, 0.50 mmol) in EA/hexane (20 mL, 1:1,v:v) was added Lindlar catalyst (200 mg) under N₂. The mixture wasstirred under H₂ (40 Psi) at 2° C. for 1.5 h. The suspension wasfiltered, and the filtrate was treated with Lindlar catalyst (200 mg)under N₂, and stirred under H₂ (40 Psi) at 25° C. for 1.5 h. The mixturewas filtered, and the filtrate was concentrated at low pressure to givecrude 221-10 (287 mg) as a white solid.

Compound 221-10 (287 mg, 0.48 mmol) was dissolved in NH₃/MeOH (30 mL, 7M). The mixture was stirred at RT for 24 h under N₂ and thenconcentrated at low pressure. The residue was purified by prep-HPLC(0.1% HCOOH in water and MeCN) to give 221-11 (50 mg, 34.7% over twosteps) as a white solid. ¹H-NMR (CD₃OD, 400 MHz) δ=7.86 (d, J=8.0 Hz1H), 6.26 (s, 1H), 5.62-5.86 (m, 1H), 5.49 (d, J=17.1 Hz, 1H), 5.30 (d,J=10.5 Hz, 1H), 4.41 (d, J=19.3 Hz, 1H), 3.71-3.86 (m, 1H).

Compound 221-11 (113 mg, 0.39 mmol) was co-evaporated with toluene 3times to remove H₂O. To a stirred solution of 221-11 (113 mg, 0.39 mmol)in a mixture of MeCN (0.5 mL) and NMI (320 mg, 3.90 mmol) was added asolution of 73-C (256 mg, 0.66 mmol) in MeCN (0.5 mL) at 0° C. Themixture was stirred at RT overnight and then concentrated at lowpressure. The residue was purified on a silica gel column (5% MeOH inDCM) to give crude 221, which purified by prep-HPLC (0.1% HCOOH in waterand MeCN) to give 221 (45 mg, 20.1%) as a white solid. ESI-MS: m/z 538.2[M-F]⁺ ESI-MS: m/z 580.2 [M+Na]⁺.

Example 151 Compound 222

To a solution of 221-9 (300 mg, 0.50 mmol) in MeOH (30 mL) was added wetPd/C (300 mg, 10%) under N₂. The mixture was stirred under H₂ (1 atm) at25° C. for 1.5 h. The suspension was filtered, and then concentrated atlow pressure to give crude 222-1 (307 mg) as a white solid.

Compound 222-1 (307 mg, 0.48 mmol) was dissolved in NH₃/MeOH (30 mL, 7M). The mixture was stirred at RT for 24 h under N₂ then concentrated atlow pressure. The residue was purified by prep-HPLC (0.1% HCOOH in waterand MeCN) to give 222-2 (30 mg, 21% over two steps) as a white solid.

Compound 222-2 (91 mg, 0.31 mmol) was co-evaporated with toluene 3 timesto remove H₂O. To a stirred solution of 222-2 (91 mg, 0.31 mmol) in amixture of MeCN (0.5 mL) and NMI (254 mg, 3.90 mmol) was added asolution 222-C (203 mg, 0.66 mmol) in MeCN (0.5 mL) at 0° C. The mixturewas stirred at RT overnight and then concentrated at low pressure. Theresidue was purified on a silica gel column (5% MeOH in DCM) to thecrude 222, which purified by prep-HPLC (0.1% HCOOH in water and MeCN) togive 222 (30 mg, 17%) as a white solid. ESI-MS: m/z 540.1 [M-F]⁺.

Example 152 Compound 226

To an ice cooled solution of 226-1 (50 g, 204.9 mmol) in dry pyridine(400 mL) was added TIPDSCl (70.78 g, 225.4 mmol) dropwise. The mixturewas stirred at RT for 16 h, and then concentrated at low pressure. Theresidue was purified by chromatography using 20% EA in PE to generate226-2 (111.5 g, 100%) as a white solid.

To a solution of 226-2 (50 g, 103 mmol) in anhydrous CH₃CN (400 mL) wasadded IBX (43 g, 153 mmol) at RT. The mixture was refluxed overnight andmonitored by TLC (PE:EA=1:1). The precipitate was filtered off, and thefiltrate was concentrated to give the crude 226-3 (50 g, 99%) as a whitesolid.

To a solution of trimethylsilylacetylene (20 g, 200 mmol) in anhydrousTHF (400 mL) was added dropwise n-BuLi (80 mL, 200 mL) at −78° C. Themixture was stirred at −78° C. for 30 mins, and then warmed to R.T for10 mins. Compound 226-3 (30 g, 60 mmol) in THF (100 mL) was added to themixture dropwise at −78° C. The mixture was stirred at −78° C. for 1 hand then slowly warmed to RT. The mixture was stirred for 20 mins, andthen the reaction was quenched with a sat. NH₄Cl solution at −78° C. Themixture was diluted with EA. The organic phase was washed with brine,dried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified by silica gel column chromatography (15% EA in PE)to give 226-4 as a white solid (14 g, 50%).

Compound 226-4 (14 g, 24 mmol) was dissolved in anhydrous toluene (100mL) under N₂ and cooled to −78° C. DAST (19 g, 120 mmol) was addeddropwise at −78° C. and stirring was continued for 1.5 h. The mixturewas diluted with EA and poured into a sat. NaHCO₃ solution. The organiclayer was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelchromatography (20% EA in PE) to give 226-5 as a white solid (12 g,81%).

A mixture of 226-5 (12 g, 20 mmol) and NH₄F (11 g, 30 mmol) in MeOH (150mL) was refluxed for 2 h. After cooling to R.T, the mixture wasconcentrated at low pressure, and the residue was purified by silica gelcolumn chromatography (5% MeOH in DCM) to give 226-6 (3.1 g, 58%) as awhite solid.

To a solution of 226-6 (3.1 g, 11.6 mmol) in dry Py (50 mL) was addedimidazole (3.1 g, 46.4 mmol) and TBSCl (5.2 g, 34.8 mmol). The mixturewas stirred at 50-60° C. for 3 h. The mixture was concentrated at lowpressure, and the residue was dissolved in EA (100 mL). The solution waswashed with brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel chromatography (20% EAin PE) to give 226-7 as a white solid (5 g, 86%).

To a solution of 226-7 (4.5 g, 9 mmol) in 1,4-dioxane (45 mL) was addedCuBr (643 mg, 4.5 mmol), dicyclohexylamine (3.3 g, 18 mmol) andparaformaldehyde (675 mg, 22.5 mmol). The mixture was refluxed for 24 hand then cooled to RT. The reaction was quenched with a sat. NH₄Clsolution. The mixture was extracted with EA (3×100 mL). The organiclayer was washed with brine, dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by silica gelcolumn chromatography (15% EA in PE) to give 226-8 as a white solid (2.0g, 43%).

A mixture of 226-8 (2 g, 4 mmol) and NH₄F (2.2 g, 60 mmol) in MeOH (20mL) was refluxed overnight. After cooling to RT, the mixture wasconcentrated at low pressure, and the residue was purified by silica gelcolumn chromatography (5% MeOH in DCM) to give 226-9 (946 mg, 83%) as awhite solid.

To a stirred suspension of 226-9 (946 mg, 3.33 mmol), PPh₃ (1.3 g, 5mmol), imidazole (453 mg, 6.66 mmol) and pyridine (3 mL) in anhydrousTHF (12 mL) was added a solution of I₂ (1 g, 4.33 mmol) in THF (4 mL)dropwise at 0° C. The mixture was warmed to RT and stirred for 16 h. Thereaction was quenched with a sat. Na₂S₂O₃ aq. solution and extractedwith EA (3×60 mL). The organic layer was dried over Na₂SO₄ andconcentrated at low pressure. The residue was purified on a silica gelcolumn (2% MeOH in DCM to 5% MeOH in DCM) to afford 226-10 (2.1 g,crude) as a white solid.

To a solution of 226-10 (2.1 g, 5.3 mmol) in THF (15 mL) was added DBU(15 g, 100 mmol) and the mixture stirred for 30 mins. The mixture wasdiluted with EA and neutralized with acetic acid. The solution waswashed with brine, dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel column chromatography(1.5% MeOH in DCM) to give 226-11 as a white solid (800 mg, 90%).

To an ice-cooled solution of 226-11 (800 mg, 3 mmol) in dry MeCN (1.5mL) was added NEt₃.3HF (484 mg, 3 mmol) and NIS (1.68 g, 7.5 mmol). Themixture was stirred at RT for 30 mins., and the reaction was monitoredby LCMS. The reaction was quenched with sat. Na₂S₂O₃ and sat. NaHCO₃solution, and extracted with EA (3×50 mL). The organic layer was driedover anhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by a silica gel column (25% EA in PE) to afford 226-12 (850 mg,68%) as a white solid.

To a solution of 226-12 (850 mg, 2 mmol) in dry DCM (10 mL) was addedDMAP (488 mg, 4 mmol) and BzCl (422 mg, 3 mol). The mixture was stirredfor 4-5 h at RT, and the reaction was monitored by LCMS. The mixture wasdiluted with CH₂Cl₂ (40 mL), and washed with a sat. NaHCO₃ solution. Theorganic layer was dried over anhydrous Na₂SO₄, and filtered. Thefiltrate was evaporated at low pressure, and the residue was purified bysilica gel column chromatography (20% EA in PE) to give 226-13 (900 mg,87%) as a white foam.

Tetra-butylammonium hydroxide (21 mL as 54-56% aqueous solution, ˜42mmol, 24 eq.) was adjusted with TFA to pH˜4 (3.5 mL), and the solutionwas treated with a solution of 226-13 (900 mg, 1.7 mmol) in DCM (21 mL).m-Chloroperbenzoic acid (2.1 g, 60-70%, ˜8.75 mmol, ˜5 eq.) was addedportionwise under vigorous stirring, and the mixture was stirredovernight. The mixture was diluted with CH₂Cl₂ (30 mL), and washed witha saturated NaHCO₃ solution. The organic layer was washed with brine,dried over anhydrous magnesium sulfate and concentrated under reducedpressure. The residue was purified by column chromatography in (40-70%EA in PE) to give 226-14 as an oil. The residue was purified by TLC (50%EA in PE) to give pure 226-14 (350 mg 50%).

Compound 226-14 (350 mg, 0.86 mg) was treated with 7N NH₃ in MeOH (15mL). The mixture was stirred for 2-3 h and monitored by TLC. The mixturewas concentrated at low pressure, and the residue was purified by silicagel column chromatography (5% isopropanol in DCM) to give 226-15 (250mg, 96%) as a white solid. ¹H NMR (CD₃OD, 400 M Hz) δ=7.75 (d, J=7.9 Hz,1H), 6.60-6.35 (m, 1H), 5.72 (d, J=8.2 Hz, 1H), 5.37-5.25 (m, 1H),5.17-5.06 (m, 1H), 5.04-4.94 (m, 1H), 4.59-4.29 (m, 1H), 3.87-3.70 (m,2H).

To a stirred solution of 226-16 (3.79 g, 18 mmol) and 226-17 (3 g, 18mmol) in anhydrous DCM (60 mL) was added with a solution of TEA (4 g, 39mmol) in DCM (40 mL) dropwise at −78° C., and the mixture was stirredfor 2 h. The mixture was concentrated at low pressure, and the residuewas dissolved in methyl-butyl ether. The precipitate was removed byfiltration, and the filtrate was concentrated to give the crude product.The residue was purified by dry column chromatography (anhydrous DCM) togive pure 226-18 as a colorless oil (3 g, 54%).

Compound 226-15 (200 mg, 0.66 mmol) was coevaporated with toluene 3times to remove H₂O. Compound 226-15 was treated with MeCN (1.5 mL) andNMI (541 mg, 6.6 mmol). The mixture was stirred at RT, and then 226-18(403 mg, 1.32 mmol) in MeCN (0.5 mL) was added. The residue was purifiedby a silica gel column (5% iPrOH in DCM) to give the crude product,which was purified by HPLC (0.1% HCOOH in water and MeCN) to give 226(33 mg, 9%). ESI-LCMS: m/z 594 [M+Na]⁺.

Example 153 Compounds 265 and 266

Into a 2000-mL round-bottom flask, was placed a solution of 269-1 (100g, 384.20 mmol, 1.00 eq.) in N,N-dimethylformamide (1000 mL) at RT. NaH(11.8 g, 491.67 mmol, 1.20 eq.) was added in several batches and themixture was stirred at 0° C. for 0.5 h. (bromomethyl)benzene (78.92 g,461.44 mmol, 1.20 eq.) was added at 0° C. and the solution was stirredovernight at RT. The reaction was quenched with water. The solution wasdiluted with EA (2000 mL), washed with aq. NaCl (3×500 mL), dried overanhydrous sodium sulfate, filtered and concentrated under reducedpressure. The crude product was purified by a silica gel column withEA:PE (1:10) to yield 269-2 (105 g, 78%).

Into a 1000-mL round-bottom flask, was placed 269-2 (100 g, 285.38 mmol,1.00 eq.), acetic acid (300 mL) and water (100 mL). The solution wasstirred overnight at RT. The mixture was then diluted with EA (2000 mL),washed with aq. NaCl (2×500 mL) and aq. sodium bicarbonate (3×500 mL),dried over anhydrous sodium sulfate, filtered and concentrated underreduced pressure. Crude 269-3 (64 g) was obtained as light yellow oil.ESI MS m/z: 333 [M+Na]⁺.

Into a 5000-mL round-bottom flask, was placed a solution of 269-3 (140g, 451.11 mmol, 1.00 eq.) in MeOH (500 mL). A solution of sodiumperiodate (135.2 g, 632.10 mmol, 1.40 eq.) in water (1000 mL) was added.The solution was stirred at R.T. for 1 h, then diluted with EA (2000mL), washed with sat. NaCl solution (3×500 mL), dried over anhydroussodium sulfate, filtered and concentrated under reduced pressure. Thesolid was dried in an oven under reduced pressure to yield crude 269-4(97 g) as yellow oil

Into a 3000-mL round-bottom flask, was placed a solution of 269-4 (100g, 359.32 mmol, 1.00 eq.) in tetrahydrofuran (500 mL) at RT. Water (500mL) was added. To the mixture was added a NaOH solution (600 mL, 2 N inwater) at 0° C. followed by aq. formaldehyde (240 mL, 37%). The solutionwas stirred overnight at RT. The mixture was diluted with EA (1500 mL),washed with sat. NaCl solution (3×500 mL), dried over anhydrous sodiumsulfate, filtered and concentrated under reduced pressure. The crudeproduct was purified by a silica gel column with EA:PE (1:1) to give269-5 (52.5 g, 47%) as a white solid. ESI MS m/z: 333 [M+Na]⁺.

Into a 3000-mL round-bottom flask, was placed a solution of 269-5 (76 g,244.89 mmol, 1.00 eq.) in acetonitrile (1500 mL) at RT. NaH (6.76 g,281.67 mmol, 1.15 eq.) was added in several batches at 0° C. Thesolution was stirred at 0° C. for 15 mins, then (bromomethyl)benzene(48.2 g, 281.82 mmol, 1.15 eq.) was added. The solution was stirredovernight at RT. The reaction was quenched with water, diluted with EA(3000 mL), washed with aq. NH₄Cl (3×500 mL), dried over anhydrous sodiumsulfate, filtered and concentrated under reduced pressure. The crudeproduct was purified by a silica gel column with EA:PE (1:5) to yield269-6 (50 g, 51%) as a yellow oil. ESI MS m/z: 423 [M+Na]+.

Into a 250-mL round-bottom flask, was placed a solution ofdiethylaminosulfur trifluoride (6.6 mL, 2.00 eq.) in toluene (10 mL) atRT. 269-6 (10 g, 24.97 mmol, 1.00 eq.) in toluene (120 mL) was added at0° C. The solution was stirred for 3 h at 60° C. in an oil bath. Themixture was cooled to 0° C., diluted with EA (300 mL), washed with sat.NaCl solution (3×50 mL), dried over anhydrous sodium sulfate, filteredand concentrated under reduce pressure. The crude product was purifiedby a silica gel column with EA:PE (1:5) to give 269-7 (5000 mg, 50%) asa yellow oil. ESI MS m/z: 425 [M+Na]⁺.

Into a 250-mL 3-necked round-bottom flask purged and maintained with aninert atmosphere of N₂, was placed 269-7 (10 g, 23.61 mmol, 1.00 eq.,95%) in acetic acid (80 mL). Acetic anhydride (6 mL) and sulfuric acid(0.05 mL) were added. The solution was stirred for 2 h at RT. Themixture was then diluted with EA (500 mL), washed with water (3×200 mL)and aq. sodium bicarbonate (3×200 mL), dried over anhydrous sodiumsulfate, filtered and concentrated under reduced pressure. The crudeproduct was purified by a silica gel column with EA:PE (1:10-1:5) toyield 269-8 (6 g, 54%) as a yellow oil. ESI MS m/z: 469 [M+Na]⁺.

Into a 50-mL round-bottom flask purged, was placed a solution of 269-8(4 g, 8.96 mmol, 1.00 eq.), 10% Pd—C catalyst (4 g) in MeOH/DCM (25mL/25 mL). To this mixture was introduced H₂ (gas) in, ˜3 atmosphericpressure. The solution was stirred for 48 h at RT. The solids werecollected by filtration, and the solution was concentrated under reducedpressure to give 269-9 (0.7 g, 29%) of as a colorless oil.

Into a 25-mL round-bottom flask, was placed 269-9 (2000 mg, 7.51 mmol,1.00 eq.), Ac₂O (8 mL), 4-dimethylaminopyridine (183.2 mg, 0.20 eq.) inpyridine (8 mL). The solution was stirred for 3 h at RT. The reactionwas a sat. sodium bicarbonate solution. The solution was diluted with EA(200 mL), washed with sat. NaCl solution (3×50 mL), dried over anhydroussodium sulfate, filtered and concentrated under reduced pressure. Thecrude product was purified by a silica gel column with EA:PE (1:7) toyield (1500 mg, 57%) of 269-10 as a white solid. ESI MS m/z: 373[M+Na]⁺.

Into a 25-mL round-bottom flask, was placed a solution of 269-10 (300mg, 0.86 mmol, 1.00 eq.) in dichloromethane (3 mL) at RT.Trimethylsilanecarbonitrile (169 mg, 1.70 mmol, 2.00 eq.) was added atR.T., followed by tetrachlorostannane (223 mg, 0.86 mmol, 1.00 eq.) at0° C. The solution was stirred at 0° C. for 3 h. The reaction wasquenched with sat. sodium bicarbonate solution. The solution was dilutedwith DCM (50 mL), washed with sat. NaCl solution (2×10 mL), dried oversodium sulfate, filtered and concentrated under reduced pressure. Thecrude product was purified by a silica gel column with PE:EA (5:1) togive 269-11 (110 mg, 40%) as a yellow oil. ¹H-NMR (400 MHz, CDCl₃): δppm 5.67˜5.75 (m, 2H), 4.25˜4.78 (m, 5H), 2.19 (s, 3H), 2.14 (s, 3H),2.10 (s, 3HI

Into a 25-mL round-bottom flask, was placed 269-11 (200 mg, 0.63 mmol,1.00 eq.), NBS (223 mg, 1.25 mmol, 2.00 eq.) in tetrachloromethane (5mL). The solution was heated under reflux for 3 h over a 250 W tungstenlamp, and then cooled to RT. The reaction was quenched sat. sodiumbicarbonate solution. The solution was EA (100 mL), washed with sat.NaCl solution (3×20 mL), dried over sodium sulfate, filtered andconcentrated under reduced pressure. The crude product was purified by asilica gel column with PE:EA (7:1) to give 269-12 (120 mg, 48%) as ayellow oil. ¹H-NMR (400 MHz, CDCl₃): δ ppm 6.03 (d, J=4.8 Hz, 1H), 5.90(d, J=4.8 Hz, 1H), 4.29-4.30 (m, 4H), 2.25 (s, 3H), 2.15 (s, 3H), 2.25(s, 3H).

Into a 25-mL round-bottom flask purged and maintained with an inertatmosphere of argon, was placed a solution ofN-(2-oxo-1,2-dihydropyrimidin-4-yl)benzamide (54.3 mg, 2.00 eq.) and(NH₄)₂SO₄ (5 mg) in HMDS (3 mL). The solution was stirred overnight at120° C. in an oil bath. The solution was concentrated under vacuum, andthe residue was dissolved DCE (1 mL) under Ar. A solution of 269-12 (50mg, 0.13 mmol, 1.00 eq.) in MeCN (1 mL) was added followed by AgOTf(32.5 mg, 1.00 eq.). The solution was stirred for 3 h at 80° C. in a10-mL sealed tube. After cooling to R.T., the solution was diluted withEA (50 mL), washed with sat. sodium bicarbonate solution (3×10 mL) andsat. NaCl (2×10 mL) solution, dried over anhydrous sodium sulfate,filtered and concentrated under reduced pressure. The crude product waspurified by a silica gel column with DCM:MeOH (15:1) to yield 269-13 (30mg, 45%) as a yellow oil. ESI MS m/z: 428 [M+H]⁺.

Into a 25-mL round-bottom flask, was placed a solution of 269-13 (100mg, 0.23 mmol, 1.00 eq.) in ACN (3 mL). 4-dimethylaminopyridine (28.5mg, 0.23 mmol, 1.00 eq.) and TEA (71 mg, 0.70 mmol, 3.00 eq.) was addedfollowed by TPSCl (212.8 mg, 0.70 mmol, 3.00 eq.). The solution wasstirred for 3 h at R.T., and then concentrated under vacuum. Crude269-14 (200 mg) was obtained as a yellow oil.

Into a 25-mL round-bottom flask, was placed a solution of 269-14 (140mg, 0.10 mmol, 1.00 eq.) in ACN (3 mL) and ammonium oxidanide (3 mL).The solution was stirred for 4 h at 35° C. in an oil bath. The mixturewas concentrated under vacuum. The crude product was purified byPrep-HPLC (Prep-HPLC-020): Column, XBridge Prep C18 OBD Column, 19*150mm 5 um 13 nm; mobile phase, WATER WITH 0.05% TFA and ACN (35.0% ACN upto 48.0% in 8 mins); Detector, nm to yield 269 (21.3 mg, 25%) as a whitesolid. ESI MS m/z: 301.1 [M+1]⁺.

Into a 25-mL round-bottom flask, was placed a solution of 269-13 (50 mg,0.12 mmol, 1.00 eq.), sat. NH₄OH (2 mL) and 1,4-dioxane (2 mL). Thesolution was stirred for 2 h at RT. After concentrated under reducedpressure, the crude product was purified by Prep-HPLC [(Prep-HPLC-020):Column, XBridge Prep C18 OBD Column, 19*150 mm 5 um 13 nm; mobile phase,WATER WITH 0.05% TFA and ACN (35.0% ACN up to 48.0% in 8 mins);Detector, nm] to yield 268 (13.6 mg, 39%) as a white solid ESI MS m/z:299.9 [M−1]⁻

Example 154 Compound 270

Nucleoside 270-1 (100 mg, 0.26 mmol) was dissolved in n-butylamine (2mL) and left for 2 h at RT. The solvent was evaporated, and the residuewas purified by RP HPLC on Synergy 4 micron Hydro-RP column(Phenominex). A linear gradient of MeOH from 10 to 60% in 50 mMtriethylammonium acetate buffer (pH 7.5) was used for elution. Thecorresponding fractions were combined, concentrated and lyophilized (3×)to remove excess of buffer and yield 270 (20 mg, 25%). MS: m/z 308[M−1].

Example 155 Compound 271

To a stirred solution of 271-1 (43.6% in dichloromethane, 345.87 g, 1.16mol) in anhydrous DCM (1.0 L) was addedethyl-2-(triphenylphosphoranylidene) propanoate (400 g, 1.100 mol)dropwise over a period of 30 mins at −40° C. The mixture was allowed towarm to 25° C. and stirred for 12 h. The mixture was concentrated underreduced pressure. The residue was suspended in TMBE (2.0 L). The solidwas removed by filtration. The filtrate was concentrated under reducedpressure. The residue was purified on silica gel column (1.2% EA in PE)to give 271-2 (191.3 g, 80.26%) as a white foam. ¹H-NMR (400 Hz, CDCl₃),δ=6.66 (dd, J=6.8, 8.0 Hz, 1H), 4.81-4.86 (m, 1H), 4.11-4.21 (m, 3H),3.60 (t, J=8.4 Hz, 1H), 1.87 (d, J=1.2 Hz, 3H), 1.43 (s, 3H), 1.38 (s,3H), 1.27 (t, J=6.8 Hz, 3H).

To a stirred solution of 271-2 (100 g, 0.47 mol) in acetone (2.0 L) wasadded KMnO₄ (90 g, 0.57 mol) in portions at 0-5° C. The mixture wasstirred at 0-5° C. for 2 h. The reaction was quenched using sat. sodiumsulfite solution (600 mL). After 2 h, a colorless suspension was formed.The solid was removed by filtration. The filter cake was washed with EA(300 mL). The filtrate was extracted with EA (3×300 mL). The organicphase was dried over anhydrous Na₂SO₄. The organic phase wasconcentrated under reduced pressure to give crude 271-3 (50 g, 43.4%) asa solid.

To a stirred solution of 271-3 (50.0 g, 0.20 mol) and triethylamine(64.0 g, 0.63 mol) in anhydrous DCM (1.0 L) was added thionyl chloride(36.0 g, 0.31 mol) at 0° C.

After 30 mins, the mixture was diluted with dichloromethane (500 mL) andwashed with cold water (1.0 L) and brine (600 mL). The organic phase wasdried over anhydrous Na₂SO₄. The organic phase was concentrated underreduced pressure to give the crude as a brown oil. To crude in anhydrousacetonitrile were added TEMPO catalyst (500 mg) and NaHCO₃ (33.87 g,0.40 mol) at 0° C. A sodium hypochlorite solution (10-13%, 500 mL) wasadded dropwise at 0° C. for 20 mins. The solution was stirred at 25° C.for 1 h. The organic phase was concentrated, and the aqueous phase wasextracted with dichloromethane (3×). The organic phase was dried overanhydrous Na₂SO₄. The solvent was removed under reduced pressure to give271-4 (53.0 g, 85.48%) as a yellow oil.

To a stirred solution of 271-4 (62.0 g, 0.20 mol) in anhydrous dioxane(1.5 L) was added TBACl (155.4 g, 0.50 mol) at 25° C. The solution wasstirred at 100° C. for 10 h. The mixture was cooled to 25° C., andtreated with 2,2-dimethoxypropane (700 mL), followed by conc. HCl (12 N,42 mL). The mixture was stirred at 25° C. for 3 h and then concentratedunder reduced pressure to give crude 271-5 as a brown oil (45.5 g,crude), which was used for next step without further purification.

Crude 271-5 (45.5 g, 171 mmol) was dissolved in a mixture of EtOH (500mL) and conc. HCl (12 N, 3.0 mL). The mixture was stirred at 25° C. for16 h. The solvent was removed under reduced pressure. The residue wasco-evaporated with toluene (3×) to give crude 271-6 (24.6 g, crude) as abrown oil, which was used for the next step.

To a stirred solution of crude 271-6 (24.6 g, crude) and DMAP (4.8 g,40.0 mmol) in anhydrous pyridine (800 mL) was added benzoyl chloride(84.0 g, 0.60 mol) dropwise over a period of 40 mins at 0° C. Themixture was stirred at 25° C. for 12 h and then concentrated at lowpressure. The residue was dissolved in EA (1.5 L). The solution waswashed with 1.0 M HCl solution (400 mL) and brine (800 mL). The organicphase was dried over anhydrous Na₂SO₄. The solvent was removed underreduced pressure to give a brown solid. The solid was suspended in MeOH(600 mL). After filtration, the filter cake was washed with MeOH. Thefilter cake was dried under reduced pressure to give 271-7 (40.0 g,75.0%) as a white solid.

To a stirred solution of 271-7 (7.0 g, 18.04 mmol) in anhydrous THF (70mL) was added a solution of lithium tri-tert-butoxyaluminohydride (27mL, 1.0 M, 27.06 mmol) dropwise over a period of 30 mins at −78° C.under N₂. The mixture was stirred at −20 OC for 1 h. The reaction wasquenched with sat. NH₄Cl aq. and diluted with EA. After filtration, thefiltrate was extracted with EA. The organic phase was dried overanhydrous Na₂SO₄, and concentrated at low pressure. The residue waspurified by silica column gel (5% EA in PE) to give 271-8 (6.8 g, 96.7%)as a colorless oil.

To a stirred solution of PPh₃ (1.34 g, 5.12 mmol) in CH₂Cl₂ (5 mL) wasadded 271-8 (1.0 g, 2.56 mmol) at −20° C. under N₂. After the mixturewas stirred for 15 mins, CBr₄ (1.96 g, 5.89 mmol) was added in portionswhile maintaining the reaction temperature between −25 and −20° C. underN₂ flow. After completion of the addition, the mixture was stirred below−17° C. for 20 mins. The reaction was treated with silica gel. Afterfiltration, the pad of silica gel was washed with CH₂Cl₂. The combinedfiltrates were purified by silica column gel (EA in PE from 2% to 25%)to give 271-9 (α-isomer, 0.5 g, 43.4%) as a colorless oil.

A 0.25 L three-neck round-bottomed flask was charged with6-chloro-9H-purin-2-amine (5.5 g, 34.75 mmol) followed by anhydroust-BuOH (45 mL) with stirring. To this solution was added potassiumtert-butoxide (3.89 g, 32.58 mmol) in portions at R.T. under N₂ flow.After 30 mins, a solution of 271-9 (4.92 g, 10.86 mmol) in anhydrousacetonitrile (30 mL) was added over a period of 5 mins at 25° C. Themixture was slowly heated to 50° C. and stirred for 12 h. The mixturewas treated with solid NH₄Cl and water, and then filtered through ashort pad of Celite. The pad was washed with EA, and the filtrates wereneutralized with aqueous 1.0 M HCl. The combined organic layers weredried over anhydrous Na₂SO₄. The organic phase was concentrated underreduced pressure. The residue was purified by silica column gel (EA inPE from 2% to 20%) to give 271-10 (1.7 g, 28.9%) as a white foam. ¹H-NMR(400 MHz, DMSO-d₆) δ=8.37 (s, 1H), 8.07-8.01 (m, 2H), 7.93-7.87 (m, 2H),7.75-7.69 (m, 1H), 7.65-7.53 (m, 3H), 7.41 (t, J=7.8 Hz, 2H), 7.13 (s,2H), 6.37 (d, J=19.3 Hz, 1H), 6.26-6.13 (m, 1H), 4.86-4.77 (m, 1H),4.76-4.68 (m, 2H), 1.3 (d, J=20 Hz, 3H).

Compound 271-10 (700 mg, 1.29 mmol) was dissolved in 4% HCl in MeOH (25mL) at 25° C. The mixture was stirred at 50° C. for 12 h. The solventwas removed under reduced pressure. The residue was purified by columnchromatography to give 271-11 (401 mg, 59.2%) as a white solid.

Compound 271-11 (250 mg, 0.477 mmol) was treated with 7.0 M NH₃ in MeOH(25 mL) at 25° C. and stirred for 18 h. The solvent was removed at lowpressure. The residue was purified by prep-HPLC (NH₄HCO₃ system) to give271 (85 mg, 56.4%) as a white solid. MS: m/z 315.7 [M+H]⁺, 630.5[2M+H]⁺.

Example 156 Compound 265

To an ice-cold solution of triethylammonium bis(POM)phosphate (7 mmol,prepared from 2.3 g of bis(POM)phosphate and 1 mL of Et₃N) and 265-1(1.36 g; 4.2 mmol) were added diisopropylethyl amine (3.6 mL; 21 mmol),BOP-Cl (2.68 g; 10.5 mmol) and 3-nitro-1,2,4-triazole (1.20 g; 10.5mmol). The mixture was stirred at 0° C. for 2 h. The mixture was thendiluted with EtOAc, washed with 1 M citric acid, sat. aq. NaHCO₃ andbrine and dried with Na₂SO₄. The evaporated residue was purified onsilica gel column with i-PrOH/CH₂Cl₂ solvent system (2-12% gradient) toyield 265-2 (2.13 g, 80%).

A solution of 265-2 (2.13 g) in 80% aq. HCOOH (10 mL) was stirred at 45°C. for 8 h. The mixture was cooled and concentrated to obtain a residue.The residue was coevaporated with toluene and MeOH containing few dropsof Et₃N. The evaporated residue was purified on silica gel column withMeOH:CH₂Cl₂ (3-10% gradient) to yield 265 as a white foam (1.1 g, 56%).MS: m/z=565 [M−1].

Example 157 Compound 273

40-1 (1.78 g, 5 mmol) and Compound A (3.22 g, 5.5 mmol; preparedaccording to the procedure provided in WO 2008/82601 A2) werecoevaporated with pyridine and then dissolved in pyridine (70 mL).Pivaloyl chloride (1.22 mL; 10 mmol) was added dropwise at −15° C., andthe mixture stirred at −15° C. for 2 h. The mixture was diluted withCH₂Cl₂, washed with 0.5 M aq. NH₄Cl and brine, and dried with Na₂SO₄.The evaporated residue was purified on a silica column withCH₂Cl₂:i-PrOH (4-10% B gradient) to afford 273-2 (2.1 g, 50%).

To a solution of 273-2 (0.51 g, 0.62 mmol) in CCl₄ (6 mL) was addedbenzylamine (0.34 mL, 3.1 mmol) dropwise, and the mixture was stirred atR.T. for 1 h. The mixture was diluted with EtOAc, washed with 0.5 M aq.citric acid, sat. aq. NaHCO₃ and brine, and dried with Na₂SO₄. Theevaporated residue was purified on a silica column with CH₂Cl₂:i-PrOH(4-10% B gradient) to afford 273-3 (0.46 g, 80%).

A mixture of 273-3 (130 mg, 0.14 mmol) and 80% aq. TFA (1.5 mL) wasstirred at R.T. for 2 h. The mixture was evaporated and coevaporatedwith toluene. The residue was purified on a silica column withCH₂Cl₂:MeOH (4-12% B gradient) to afford 273 (32 mg (37%). MS: m/z=620[M+1]⁺.

Example 158 Compound 274

A solution of Z-Ala-OH (111.6 mg, 0.5 mmol) in anhydrous THF (2 mL) wastreated with carbonyldiimidazole (81 mg, 0.5 mmol). The mixture wasstirred for 1 h at 40° C. under an Ar atmosphere. This solution wasadded to a solution of 44 (200 mg, 0.33 mmol), Et₃N (72 μL, 0.5 mmol)and DMAP (4 mg) in DMF (2 mL). The mixture was stirred at R.T. for 2.5h. The reaction was quenched by the addition of 1M citric acid (2 mL) at0 to 5° C. (ice/water bath) and diluted with EA. The organic layer wasseparated, washed with sodium bicarbonate and brine, dried over MgSO₄,filtered and concentrated. The residue was purified by columnchromatography in 40 to 90% EA-hexane to give 274-1 (202 mg, 76%) as awhite foam.

To a solution of 274-1 (50 mg, 0.062 mmol) in anhydrous EtOH (2 mL), wasadded 10% Pd/C (5 mg), followed by addition of 4N HCl (31 μL, 0.124mmol), and the mixture was stirred under H₂ atmosphere for 1 h. Aftercompletion of the reaction, the mixture was filtered through celite. Thecatalyst cake was washed with anhydrous EtOH. The washings and thefiltrate were combined, and the solvent was removed under vacuum to give274 (33.3 mg, 79.7%) as an off white foam. MS: m/z=674.1[M+H]⁺, 1347.2[2M+H]⁺.

Example 159 Compound 275

A solution of Z-Gly-OH (105 mg, 0.5 mmol) in anhydrous THF (2 mL) wastreated with carbonyldiimidazole (81 mg, 0.5 mmol). The mixture wasstirred for 2 h at 40° C., followed by 30 mins at 80° C. under an Aratmosphere. This solution was added to a solution of 44 (200 mg, 0.33mmol), Et₃N (72 μL, 0.5 mmol) and DMAP (4 mg) in DMF (2 mL). The mixturewas stirred at R.T. for 3 h. The reaction was quenched by the additionof 1M citric acid (2 mL) at 0 to 5° C. (ice/water bath) and diluted withEA. The organic layer was separated, washed with sodium bicarbonate andbrine, dried over MgSO₄, filtered and concentrated. The residue waspurified by column chromatography in 40 to 90% EA-hexane to give 275-1(208.5 mg, 79.6%) as an off white foam.

To a solution of 275-1 (75 mg, 0.094 mmol) in anhydrous EtOH (3 mL), wasadded 10% Pd/C (10 mg), followed by the addition of 4N HCl (47 μL, 0.19mmol). The mixture was stirred under H₂ atmosphere for 3 h. Aftercompletion of reaction, the mixture was filtered through celite. Thecatalyst cake was washed with anhydrous EtOH. The washings and thefiltrate were combined, and the solvent was removed under vacuum to give275 (44.3 mg, 71.5%) as an off white foam. MS: m/z=658.05[M+H]⁺,1317.05[M+H]⁺.

Example 160 Compound 276

To a solution of 273-2 (223 mg, 0.27 mmol) in CCl₄ (3 mL) were addedL-alanine isopropyl ester hydrochloride (135 mg, 0.8 mmol) and dropwiseEt₃N (0.22 mL, 1.6 mmol). The mixture was stirred at R.T. for 1 h. Themixture was then diluted with CH₂Cl₂, washed with sat aq. NaHCO₃ andbrine, and dried with Na₂SO₄. The evaporated residue was purified on asilica column with CH₂Cl₂:i-PrOH (3-10% B gradient) to afford 276-1(0.16 g, 62%).

A mixture of 276-1 (100 mg, 0.11 mmol) and 80% aq. TFA (3 mL) wasstirred at R.T. for 2 h. The mixture was then evaporated andcoevaporated with toluene. The residue was purified on a silica columnwith CH₂Cl₂:MeOH (4-10% B gradient) to afford 276 (31 mg, 46%). MS:m/z=644 [M+1]⁺.

Example 161 Compounds 277 and 306

To a solution of 40-1 (1.08 g, 3.0 mmol) in N,N-dimethylacetamide (15mL) was added CsCO₃ (1.22 g, 3.7 mmol), and the mixture was stirred atR.T. for 15 mins. Dibenzyl chloromethylphosphate (1 g, 3.0 mmol) wasadded, and the mixture was stirred overnight at 40° C. After cooling,the mixture was diluted with methyl tert-butylether and washed withwater (3×) and brine, and dried with Na₂SO₄. The crude evaporatedresidue was purified on a silica column with CH₂Cl₂:i-PrOH (3-10% Bgradient) to yield 277-1 (580 mg, 30%).

To a solution of triethylammoniumbis(isopropyloxycarbonyloxymethyl)phosphate (1.8 mmol, prepared from0.60 g of bis(isopropyloxycarbonyloxymethyl)phosphate and Et₃N) in THFwas added 277-1 (0.58 g, 0.9 mmol). The mixture was evaporated andrendered anhydrous by coevaporating with pyridine follow by toluene. Theevaporated residue was dissolved in anhydrous THF (9 mL) and cooled inan ice-bath. Diisopropylethyl amine (0.94 mL, 5.4 mmol) was added,followed by BOP-Cl (0.69 g, 2.7 mmol) and 3-nitro-1,2,4-triazole (0.31g, 2.7 mmol). The mixture was stirred at 0-5° C. for 2 h, diluted withEtOAc, washed with sat. aq. NaHCO₃ and brine, and dried with Na₂SO₄. Theevaporated residue was purified on a silica column with CH₂Cl₂:i-PrOH(3-10% B gradient) to yield 277-2 (0.77 g, 89%).

To a solution of 277-2 (50 mg; 0.05 mmol) in EtOH (2.5 mL) was added 10%Pd/C (8 mg), and the mixture was stirred under H₂ (atmospheric pressure)for 1 h. The mixture was filtered through a Celite pad, and the filtratewas evaporated. The residue was treated with 80% aq. HCOOH (2.5 mL) for3 h, then evaporated and purified by RP-HPLC (A: 50 mM aq. TEAA, B: 50mM TEAA in MeCN) to afford 277 (22 mg, 44%) as a white solid. MS:m/z=713 [M+1]⁺.

To a solution of 277 (14 mg, 0.02 mmol) in EtOH (0.3 mL) at 0° C. wasadded dropwise 0.1 M EtONa in EtOH (0.4 mL; 0.04 mmol). The mixture wasallowed to warm to RT and the resulting white solid centrifuged. Thesupernatant was discarded. The solid was treated with EtOH (0.3 mL) andcentrifuged to yield 306 (8 mg). MS: m/z=713 [M+1]⁺.

Example 162 Compound 278

To a stirred suspension of 278-1 (300 g, 1.86 mol) in acetone (4 μL) wasadded conc. H₂SO₄ (56 mL) dropwise at RT. The mixture was stirred atR.T. for 3 h. The mixture was neutralized with solid NaHCO₃ andfiltered. The filtrate was evaporated under reduced pressure to give278-2 (381 g, crude) as a colorless oil, which was used for the nextstep without further purification.

To a stirred solution of 278-2 (380 g, crude, 1.88 mol) in anhydrous DCM(2 μL) was added imidazole (191 g, 2.82 mol) and TBSCl (564 g, 3.76 mol)at 0° C. The mixture was stirred at R.T. for 12 h, and then filtered.The filtrate was concentrated to dryness, and the residue was purifiedby silica gel column (2% EA in PE) to give 278-3 (569 g, 97% in 2 steps)as a white solid.

To a solution of 278-3 (150 g, 0.47 mol) in anhydrous THF (2 μL) wasadded DIBAL-H (710 mL, 0.71 mol, 1.0 M in toluene) at −78° C. for 3 h.The reaction was quenched with sat. aq. NH₄Cl and then filtered. Thefiltrate was extracted with EA and washed with brine. The organic layerwas dried over Na₂SO₄ and filtered. The filtrate was concentrated todryness. The residue was purified by silica gel column (11% EA in PE) togive 278-4 (121 g, 80.5%) as a white solid.

Isopropyltriphenylphosphonium iodide (422.8 g, 0.98 mol) was suspendedin anhydrous THF (1 L) and cooled to 0° C. A BuLi solution (2.5M in THF,391 mL, 0.98 mol) was added dropwise over 0.5 h. The deep red solutionwas maintained at 0° C. for 0.5 h and 278-4 (207.5 g, 0.65 mol) in THF(1 L) was added slowly over 2 h. The mixture was warmed to ambienttemperature and stirred for 12 h. The reaction was quenched with sat.aq. NaHCO₃. The precipitated solid was removed by filtration. Thefiltrate was diluted with EA and washed with brine. The organic layerwas dried over anhydrous Na₂SO₄ and filtered. The filtrate wasconcentrated at low pressure, and the residue was purified bychromatography on silica gel (10% to 30% EA in PE) to give 278-5 (104.7g, 47%) as a colorless oil.

To a stirred solution of 278-5 (4.9 g, 14.2 mmol) in anhydrous MeCN (70mL) was added IBX (7.9 g, 28.4 mmol). The mixture was refluxed for 2 h.The mixture was filtered, and the filtrate was concentrated to dryness.The residue was purified by column chromatography (1% EA in PE) to give278-6 (4.6 g, 94.8%) as a colorless oil.

To a stirred solution of 278-6 (2.0 g, 5.8 mmol) and difluoromethylphenyl sulfone (2.24 g, 11.7 mmol) in anhydrous DMF (50 mL) was addedLiHMDS (1.0 M in THF, 11.7 mL) dropwise at −78° C. After stirring at−78° C. for 2 h, the reaction was quenched with sat. aq. NH₄Cl. Themixture was then stirred at 0° C. for 30 mins. The organic phase wasseparated, and the aqueous phase was extracted with EA. The combinedorganic phase was washed with brine, dried over Na₂SO₄ and filtered. Thefiltrate was concentrated to dryness. The residue was purified on asilica gel chromatography (0.25% EA in PE) to give 278-7 (1.1 g, 32.1%)as a colorless oil. ¹H-NMR (CDCl₃, 400 MHz) δ=8.01-7.97 (m, 2H),7.74-7.70 (m, 1H), 7.61-7.57 (m, 2H), 5.80 (d, J=1.6 Hz, 1H), 4.26 (d,J=11.2 Hz, 1H), 4.08 (s, 1H), 4.03 (d, J=11.2 Hz, 1H), 3.86 (s, 1H),1.82 (s, 3H), 1.69 (s, 3H), 1.54 (s, 3H), 1.41 (d, J=12.4 Hz, 6H), 0.89(s, 9H), 0.09 (d, J=9.6 Hz, 6H).

To a stirred solution of 278-7 (4.0 g, 7.5 mmol) in DMF (80 mL) and H₂O(16 mL) was added Mg (3.6 g, 149.8 mmol) followed by the addition ofHOAc (13.5 g, 224.7 mmol). The mixture was stirred at R.T. for 6 h. Themixture was poured into ice water and filtered. The filtrate wasextracted with EA. The combined organic phase was washed with brine,dried over Na₂SO₄ and filtered. The filtrate was concentrated todryness, and the residue was purified on the silica gel chromatography(0.2% EA in PE) to give 278-8 (1.12 g, 38%) as a colorless oil. ¹H-NMR(CDCl₃, 400 MHz) δ=5.88-5.74 (m, 2H), 3.98-3.78 (m, 3H), 3.30 (s, 1H),3.08 (s, 1H), 1.83 (s, 3H), 1.70 (s, 3H), 1.41 (s, 3H), 1.35 (d, J=23.2Hz, 6H), 0.90 (d, J=4.4 Hz, 9H), 0.08 (d, J=7.6 Hz, 6H).

To a solution of 278-8 (1.12 g, 2.84 mmol) was added a solution (6 mL,1.0 M) of TBAF in THF, and the mixture was stirred at R.T. for 30 mins.The mixture was concentrated to dryness, and the residue was purified bysilica gel column chromatography (3% EA in PE) to give 278-9 (332 mg,41.7%) as a colorless oil.

To a solution of 278-9 (415 mg, 1.5 mmol) in anhydrous DCM (7.5 mL) wasadded Et₃N (224 mg, 2.2 mmol) and BzCl (248 mg, 1.7 mmol) at 0° C. Themixture was stirred at R.T. for 4 h. After the reaction was completed,the reaction was quenched with sat. aq. NaHCO₃ and extracted with DCM.The organic layer was dried over Na₂SO₄ and filtered. The filtrate wasevaporated, and the residue was purified by silica gel columnchromatography (1% EA in PE) to give 278-10 (441 mg, 77.4%) as colorlessoil.

To a stirred solution of 278-10 (440 mg, 1.2 mmol) in anhydrous DCM (10mL) was bubbled O₃ at −78° C. until the solution turned blue. Thereaction was then bubbled with O₂ until the solution turned tocolorless. The organic layer was evaporated to give 278-11 (430 mg,crude), which was used for next step without further purification.

278-11 (441 mg, 1.2 mmol) in 90% TFA (6 mL) was stirred at R.T. for 12h. The mixture was concentrated under reduced pressure. The residue waspurified via silica gel chromatography (50% EA in PE) to give 278-12(404 mg, 97%) as a colorless oil.

To a solution of 278-12 (404 mg, 1.3 mmol) in anhydrous DCM (6 mL) wasadded Et₃N (1.0 g, 10.2 mmol), DMAP (44 mg, 0.4 mmol) and BzCl (1.0 g,7.6 mmol) at 0° C. The mixture was stirred at R.T. for 4 h. The reactionwas quenched with sat. aq. NaHCO₃ and extracted with DCM. The organiclayer was dried over anhydrous Na₂SO₄ and filtered. The filtrate wasevaporated, and the residue was purified by silica gel columnchromatography (1% EA in PE) to give 278-13 (530 mg, 66.2%) as a lightyellow foam.

To a stirred solution of uracil (190 mg, 1.7 mmol) in chlorobenzene (2.6mL) was added N, O-bis(trimethylsilyl) acetamide (680 mg, 3.3 mmol). Thesolution was stirred at 130° C. for 30 mins, and then cooled to ambienttemperature. To a solution of 278-13 (536 mg, 0.8 mmol) in chlorobenzenewas added SnCl₄ (770 mg, 3.5 mmol) slowly dropwise. The mixture washeated to reflux for 30 mins. The reaction was quenched by sat. aq.NaHCO₃ and extracted with EA. The organic layer was dried over anhydrousNa₂SO₄ and filtered. The filtrate was evaporated, and the residue waspurified by silica gel column chromatography (20% EA in PE) to give278-14 (336 mg, 64.6%) as a white solid.

278-14 (80 mg, 0.1 mmol) was treated with 7.0 M NH₃ in MeOH. The mixturewas stirred at R.T. for 12 h. The solvent was removed at low pressure.The residue was purified by silica gel column chromatography (5% MeOH inDCM) to give 278 (36 mg, 90.6%) as a white solid. ESI-LCMS: m/z 309.09[M+H]⁺; 331.07 [M+Na]⁺.

Example 163 Compound 279

To a mixture of 51 (240 mg, 0.8 mmol) in trimethyl phosphate (4 mL) at0° C. was added POCl₃ (0.18 mL, 1.6 mmol), and the mixture was stirredat 0° C. for 90 mins. L-alanine isopropyl ester hydrochloride (0.24 g,1.4 mmol) and Et₃N (0.6 mL, 4.3 mmol) were added. The mixture was warmedto R.T. and stirring was continued for 1.5 h. The reaction was quenchedwith 0.5 M aq. TEAA, and the mixture purified by RP-HPLC (A: 50 mM aq.TEAA, B: 50 mM TEAA in MeCN) to yield 279-1 (75 mg).

A mixture of 279-1 (52 mg, 0.1 mmol), DIPEA (0.11 mL, 0.6 mmol) andisopropyloxycarbonyloxymethyl iodide (77 mg, 0.3 mmol) in NMP (1.1 mL)was stirred at R.T. for 1 h. The mixture was diluted with tert-butylmethylether, washed with sat. aq. NaHCO₃ and brine, and dried withNa₂SO₄. The evaporated residue was purified on a silica column withCH₂Cl₂:MeOH (4-10% B gradient) to yield 279 (12 mg, 20%). MS: m/z=600[M+1]⁺.

Example 164 Compound 280

To a solution of 44 (200 mg, 0.33 mmol) in anhydrous DCM (6 mL) wasadded DMAP (4 mg, 0.033 mmol), N-Cbz-O-benzyl-L-serine (164 mg, 0.5mmol) and EDC (100 mg, 0.52 mmol) at 0 to 5° C. (ice/water bath). Themixture was stirred for 40 h at RT. The mixture was cooled usingice/water bath, diluted with DCM (10 mL), washed sat. NH₄Cl, dried overMgSO₄, filtered and concentrated. The residue was purified by columnchromatography in 50 to 90% EA-hexane to give 280-1 (187 mg, 62%) as awhite foam.

To a solution of 280-1 (68.7 mg, 0.075 mmol) in anhydrous EtOH (2.5 mL),was added 10% Pd/C (11.4 mg), followed by the addition of 4N HCl (38 μL,0.15 mmol), and the mixture was stirred under H₂ atmosphere for 3 h.After completion of reaction, the mixture was filtered through celite.The catalyst cake was washed with anhydrous EtOH. The washings andfiltrate were combined, and the solvent was removed under vacuum to give280 (40.1 mg, 77.6%) as an off white foam. MS: m/z=690.1[M+H]⁺.

Example 165 Compound 281

To a mixture of Compound B (0.84 g, 2 mmol; prepared according toVillard et al., Bioorg. Med. Chem. (2008) 16:7321-7329) and Et₃N (0.61mL, 4.4 mmol) in THF (5 mL) at −78° C. was added dropwise a solution ofN,N-diisopropyl dichlorophosphoroamidite (184 μL, 1 mmol) in THF (7 mL).The mixture was allowed to warm up and stirred at R.T. for 2 h. Thesolids were filtered off. The filtrate was concentrated and purified ona silica gel column with hexanes+1% Et₃N:EtOAc (1-20% B gradient) toyield Compound C (0.38 g).

To a mixture of 40-1 (53 mg, 0.15 mmol) and Compound C (0.17 g, 0.17mmol) in MeCN (1 mL) was added 5-ethylthio-1H-tetrazole (0.25 M in MeCN;1.2 mL, 0.3 mmol). The mixture was stirred for 1 h at R.T. and thencooled to −40° C. A solution of MCPBA (77%; 42 mg, 0.19 mmol) in CH₂Cl₂(0.5 mL) was added. The mixture was allowed to warm up and stirred atR.T. for 30 mins. The reaction was quenched with 4% aq. Na₂S₂O₃ in 4%aq. NaHCO₃ (1 mL) and diluted with CH₂Cl₂. The organic layer was washedwith sat. aq. NaHCO₃ and brine, and dried with Na₂SO₄. Purification ofthe evaporated residue on a silica gel column with hexanes:EtOAc(30-100% B gradient) yielded 281-1 (150 mg, 81%).

A solution of 281-1 (120 mg, 0.1 mmol) in 80% aq. TFA (5 mL) was kept atR.T. for 3 h. The mixture was concentrated, and the residue coevaportedwith toluene. The crude material was purified on a silica column withCH₂Cl₂:MeOH (4-10% B gradient) to give 281 (25 mg, 36%). MS: m/z=691[M+1]⁺.

Example 166 Compound 283

To a mixture of DCC (412 mg, 1.98 mmol) in DMF (1 mL), DMAP (244 mg,1.98 mmol) and Z-Val-OH (502 mg, 1.98 mmol) were added successively,followed by the addition of 44 (200 mg, 0.183 mmol). The mixture wasstirred at R.T. for 1 h. The mixture was filtered, and the filtrate wasconcentrated with a rotary evaporator until ½ of its original volume. EAwas added, and the mixture was washed with water and brine, dried overanhydrous Na₂SO₄ and concentrated in vacuo to give a residue. Theresidue was purified by silica gel with 35-95% EA:hexanes to give 283-1(107 mg, 31.2%) as a white foam.

To a solution of 283-1 (68 mg, 0.064 mmol) in anhydrous EtOH (2.0 mL)was added 10% Pd/C (12 mg), followed by the addition of 4N HCl (67 μl,0.25 mmol). The mixture was stirred under H₂ atmosphere for 1.5 h. Themixture was filtered through celite, and the catalyst cake was washedwith anhydrous EtOH. The washings and the filtrate were combined. Thesolvent was removed under vacuum to give 283 (41.6 mg, 82%) as a lightyellow foam. MS: m/z=801.25 [M+H]⁺.

Example 167 Compound 284

To a solution of 284-1 (40 mg, 0.144 mmol) in DMF (2 mL) were added DCC(65 mg, 0.32 mmol), isobutyric acid (28 μl, 0.32 mmol) and DMAP (18 mg,0.144 mmol). The mixture was stirred at R.T. overnight. The mixture wasfiltered, and the filtrate was concentrated with a rotary evaporator to½ of its original volume. The mixture was then diluted with 25% DMF/H₂Oand purified on a reverse-phase HPLC (C18) using CH₃CN and water.Lyophilization gave 284 (17.5 mg, 29%) as a white powder. MS: m/z 416.1[M+H]⁺.

Example 168 Compound 285

To a solution of 284-1 (50 mg, 0.18 mmol) in DMF (1.5 mL) were added DCC(93 mg, 0.45 mmol), propanoic acid (33.4 μl, 0.45 mmol) and DMAP (22 mg,0.18 mmol). The mixture was stirred at R.T. overnight. The mixture wasfiltered, and then filtrate was concentrated with a rotary evaporator to½ of its original volume. The mixture was then diluted with 25% DMF/H₂O,and purified on a reverse-phase HPLC (C18) using CH₃CN and water.Lyophilization gave 285 (30.2 mg, 43%) as a white powder. MS: m/z 390.1[M+H]⁺, 388.05 [M−H]⁻.

Example 169 Compound 286

To a solution of 75 (20 mg, 0.073 mmol) in DMF (0.7 mL) were added DCC(37.6 mg, 0.183 mmol), isobutyric acid (16 μl, 0.183 mmol) and DMAP (9mg, 0.073 mmol). The mixture was stirred at R.T. overnight. The mixturewas filtered, and the filtrate was concentrated with a rotary evaporatorto ½ of its original volume. The mixture was then diluted with 25%DMF/H₂O, and purified on a reverse-phase HPLC (C18) using 25-95%CH₃CN:water. Lyophilization gave 286 (12.1 mg, 38.7%) as a white powder.MS: m/z 430.15 [M+H]⁺, 428.10 [M−H]⁻.

Example 170 Compound 287

To a solution of 75 (20 mg, 0.073 mmol) in DMF (0.7 mL) were added DCC(37.6 mg, 0.183 mmol), propanoic acid (13.5 μl, 0.183 mmol) and DMAP (9mg, 0.073 mmol). The mixture was stirred at R.T. overnight. The mixturewas filtered, and then filtrate was concentrated with a rotaryevaporator to ½ of its original volume. The mixture was then dilutedwith 25% DMF/H₂O, and purified on a reverse-phase HPLC (C18) using25-95% CH₃CN:water Lyophilization gave 287 (14.1 mg, 48%) as a whitepowder. MS: m/z 402.1 [M+H]⁺.

Example 171 Compound 288

To a mixture of Compound D (0.9 g, 6.0 mmol; prepared according to Qinget al., Org. Lett. (2008) 10:545-548) and POCl₃ (0.55 mL, 6.0 mmol) indiethyl ether (9 mL) at −78° C. was added Et₃N (0.84 mL, 6.0 mmol). Themixture was allowed to warm to R.T. in 2 h. The mixture was thenfiltered, and the solids were washed with Et₂O. The combined filtrateswere evaporated, and the crude Compound E was used without purification.

To a solution of crude Compound E and L-alanine isopropyl esterhydrochloride (1.0 g, 6.0 mmol) in CH₂Cl₂ (15 mL) at −20° C. was addedEt₃N (1.67 mL, 1.2 mmol). The mixture was allowed to warm up andstirring at R.T. for 2 h. The mixture was diluted with hexanes andfiltered through a silica pad which was thoroughly washed withCH₂Cl₂:hexanes 1:1. The combined filtrates were concentrated andpurified on a silica column with hexanes:EtOAc (5-50% B gradient) toyield Compound F (0.78 g, 38% for 2 steps).

To a solution of 40-1 (0.36 g, 1.0 mmol) in THF (7.5 mL) at 0° C. wasadded isopropyl magnesium chloride (2 M in THF; 0.65 mL, 1.3 mmol), andthe mixture was stirred at 0° C. for 30 mins. A solution of Compound F(0.78 g, 2.2 mmol) in THF (2 mL) was added, and the mixture stirred atR.T. for 2 h. The reaction was quenched with sat. aq. NH₄Cl, and thendiluted with EtOAc. The two layers were separated. The organic layer waswashed with water and brine, and dried over Na₂SO₄. Purification of theevaporated residue on a silica gel column with CH₂Cl₂:i-PrOH (3-10% Bgradient) yielded 288-1 (0.50 g, 74%).

A solution of 288-1 (0.28 g, 0.4 mmol) in 80 aq. TFA (4 mL) was stirredat R.T. for 4 h. The mixture was evaporated and coevaporated withtoluene. The residue was purified on a silica column with CH₂Cl₂:MeOH(4-10% B gradient) to give 294-2 (0.17 g, 68%).

To a solution of 288-2 (85 mg, 0.14 mmol) in EtOH (3 mL) and HCl (4 N indioxane; 35 μL, 0.14 mmol) was added 10% Pd/C (8 mg). The mixture wasstirred under H₂ (atmospheric pressure) for 105 mins. The mixture wasthen filtered through a Celite pad. The evaporated residue was treatedwith Et₂O to yield 288 (55 mg, 63%) as a white solid. MS: m/z=589[M+1]⁺.

Example 172 Compound 289

A mixture of 289-1 (120 g, 0.26 mol) and IBX (109 g, 0.39 mol) in CH₃CN(2.0 L) was heated to reflux and stirred for 12 h. After cooling toR.T., the mixture was filtered. The filtrate was concentrated at lowpressure and used directly for the next step.

289-2 (130 g, crude, 0.26 mol) was co-evaporated with anhydrous toluene(3×) to remove H₂O. Vinyl magnesium bromide (700 mL, 0.78 mol, 1.0 N inTHF) was added dropwise into a solution of 289-2 in THF (300 mL) over 30mins at −78° C. The mixture was stirred for about 1 h. at 25° C. andchecked by LCMS trace. When the starting material was consumed, themixture was poured into a sat. NH₄Cl solution, and extracted with EA(3×300 mL). The organic layer was washed with brine, dried withanhydrous Na₂SO₄, filtered and concentrated at low pressure to give thecrude intermediate without further purification.

To a solution of this crude intermediate (170 g, 0.346 mol) in anhydrousCH₂Cl₂ was added TEA (105 g, 1.04 mol) and DMAP (84 g, 0.69 mol), andthe mixture was stirred at RT. Benzoyl chloride (146 g, 1.04 mol) wasadded slowly at RT. After stirring for 12 h at R.T., the mixture wasdiluted with CH₂Cl₂ and then washed with sat. aq. NaHCO₃. The combinedaqueous phase was extracted with DCM (100 mL). The combined organicphase was dried with anhydrous Na₂SO₄, filtered and evaporated todryness under reduced pressure. The residue was purified by columnchromatography (PE:EA=10:1 to 5:1) to give 289-3 (107 g, 52%).

A mixture of uracil (treated by toluene twice) and NOBSA (81.4 g, 0.4mol) in CH₃CN (200 mL) was stirred to reflux for 1.5 h. After themixture was cooled to R.T., 289-3 (59 g, 0.1 mol, treated by toluene) inCH₃CN (100 mL) was added. The mixture was treated with TMSOTf (155 g,0.7 mol), and then warmed to 60-70° C. for 12 h. LCMS showed that nostarting material remained. The mixture was poured into a NaHCO₃ (sat.)solution. The desired product precipitated. After filtration, pure 289-4(40 g, 69%) was obtained as a white solid.

To a solution of 289-4 (50 g, 0.086 mol), K₂CO₃ (17.8 g, 0.13 mol) inDMF (500 mL) was added PMBCl (16 g, 0.1 mol) at 0° C., and the mixturestirred at 25° C. for 12 h. The reaction was quenched with water, andthe mixture was extracted with EtOAc (3×150 mL). The solution was washedwith brine, dried over anhydrous Na₂SO₄ and concentrated at lowpressure. Crude 289-5 (65 g) was obtained and used directly for the nextstep.

A mixture of 289-5 (65 g, 0.086 mol) and NaOMe (16.8 g, 0.3 mol) inMeOH:DCM (4:1, 200 mL) was stirred at R.T. for 2.5 h. LCMS showed thatno starting material remained. The reaction was quenched with dry ice.The solution was washed with brine, dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The residue was purified by columnchromatography (DCM:MeOH=50:1 to 20:1) to give 289-6 as a yellow foam(25 g, 75%).

To a solution of 289-6 (25.5 g, 0.065 mol) in DMF was added NaH (10.5 g,0.26 mol) slowly at ice bath, and the mixture was stirred for 30 mins.BnBr (36.3 g, 0.21 mol) was added, and the mixture was stirred at 25° C.for 12 h. TLC showed that the starting material disappeared. Thereaction was quenched by sat. aq. NH₄Cl and extracted with EtOAc (3×100mL). The organic phase was washed with brine, dried over anhydrousNa₂SO₄ and concentrated at low pressure. The residue was purified bycolumn chromatography (PE:EA=5:1 to 3:1 to 1:1) to give 289-7 (20 g,46%).

To a solution of 289-7 (20 g, 0.03 mol), NMMO (7 g, 0.06 mol) in THF:H₂O(5:1, 100 mL) was added OsO₄ (2.6 g, 0.01 mol) at 25° C., and themixture was stirred at 25° C. for 24 h. The reaction was quenched with asat. Na₂S₂O₃ solution, and extracted with EtOAc (3×100 mL). The organiclayer was washed with brine, dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The diol product residue was used directlyfor next step.

To a solution of diol product (0.03 mol) in MeOH:H₂O:THF (170 mL:30mL:50 mL) was added NaIO₄ (9.6 g, 0.045 mol), and the mixture wasstirred at 25° C. for 2 h. After the white solid was filtered, thefiltrate was used directly for the next step.

The previous solution was treated with NaBH₄ (1.8 g, 0.048 mol) at 0°C., and stirred at 25° C. for 30 mins. The reaction was quenched withHCl (1 N) solution and adjusted pH to 7-8. The solution was extracted byEtOAc (3×50 mL). The organic phase was washed with brine washed withbrine, dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified by column chromatography (PE:EA=6:1 to 4:1) to give289-8 (12 g, 61% over 3 steps).

To a solution of 289-8 (14 g, 21 mmol), DMAP (5.1 g, 42 mmol) in DCM (50mL) was added MsCl (3.1 g, 27 mmol) at 0° C., and the mixture wasstirred at 25° C. for 40 mins. LCMS shows that no starting materialremained. The reaction was quenched by sat. aq. NaHCO₃ and extractedwith DCM (3×100 mL). The solution was washed with HCl (0.2 N) solution,dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified by column chromatography (PE:EA=10:1 to 5:1) togive the OMs-product (14 g, 90%).

The OMs-product (6.1 g, 8.21 mmol) was dissolved in TBAF (Alfa, 1 N inTHF, 120 mL), and the mixture was stirred at 70-80° C. over 3 days. LCMSshows that 50% of the starting material was converted to the desiredproduct. The mixture was concentrated at low pressure. The residue wasdissolved in EtOAc (100 mL). The solution was washed by brine, driedover anhydrous Na₂SO₄ and concentrated at low pressure. The residue waspurified by column chromatography (PE:EA=10:1 to 5:1) to give 289-9 (1.3g, 24%).

To a solution of 289-9 (6.3 g, 9.45 mmol) in CAN:H₂O (v:v=3:1, 52 mL)was added CAN (15.5 g, 28.3 mmol), and the mixture was stirred at R.T.overnight. The reaction was quenched with water, and extracted with EA(3×80 mL). The organic phase was washed with brine, dried over anhydrousNa₂SO₄ and concentrated at low pressure. The residue was purified bycolumn chromatograph (25% EA in PE) to give 289-10 (3.6 g, 71%) as ayellow oil.

To a solution of 289-10 (566 mg, 1.04 mmol), DMAP (253 mg, 2.07 mmol)and TEA (209 mg, 2.07 mmol) in anhydrous MeCN (6 mL) was added TPSCl(627 mg, 2.07 mmol) at 0° C. The mixture was stirred at R.T. for 2 h.The mixture was treated with NH₃.H₂O (10 mL), and stirred at R.T.overnight. TLC showed that the reaction was completed. The solution wasconcentrated at low pressure. The residue was purified by silica gelcolumn chromatography (DCM:MeOH=50:1 to 20:1) to give 289-11 (300 mg,49%) as a white solid.

To a solution of 289-11 (200 mg, 0.37 mmol) in anhydrous DCM (0.5 mL)was added BCl₃ (2.5 mL, 1 N in DCM) at −70° C., and the mixture wasstirred for 2 h at −70° C. TLC showed that no materials remained. Thereaction was quenched with MeOH at −70° C., and concentrated at lowpressure directly under 40° C. The residue was dissolved in H₂O, andwashed with EtOAc over 3 times. The aqueous phase was lyophilized togive 289 (91 mg, 89%) as a white solid. ESI-LCMS: m/z 276.1 [M+H]⁺.

Example 173 Compound 290

To a stirred solution of 290-1 (8.2 g, 15.3 mmol) in anhydrous CH₃CN(150 mL) was added IBX (4.7 g, 16.8 mmol) at 20° C. under N₂. Thesuspension was heated to 90° C.˜100° C. and stirred at this temperaturefor 1 h. The mixture was filtered, and the filtrate was concentratedunder reduced pressure. The residue, 290-2, (8.2 g, crude) was used inthe next step without further purification.

To a solution of 290-2 (8.2 g, 15.4 mmol) in 1,4-dioxane (150 mL) wasadded aq. NaOH (15.4 mL, 2 M, 30.8 mmol) at 20° C. The mixture wasstirred at this temperature for 10 h. The solution was neutralized withAcOH to pH=7, followed by addition of EtOH (50 mL) and NaBH₄ (5.8 g,154.3 mmol) at 0° C. The mixture was stirred at this temperature for 1h. The reaction was quenched with water (20 mL), extracted with EA (2×40mL). The combined organic phase was washed with brine, dried overanhydrous MgSO₄ and concentrated at low pressure. The residue waspurified via silica gel chromatography (50% EA in PE) to give 290-3 (5.5g, 62.92%) as a white solid.

290-3 (480 mg, 0.8 mmol) was co-evaporated with toluene (2×). Theresidue was dissolved in anhydrous DCM (5 mL) and pyridine (671 mg, 85mmol). Tf₂O (481 mg, 187 mmol) was added dropwise at 0° C. over 10 mins.The mixture was stirred at this temperature for 40 mins. The mixture waspurified by column chromatography (20% EA in PE) to give 290-4 (602 mg,86.1%) as a brown foam.

To a solution of 290-4 (602.0 mg, 0.72 mmol) in anhydrous DMF (8 mL) wasadded NaH (34.8 mg, 0.87 mmol) at 0° C. under N₂ atmosphere. Thereaction was stirred at 20° C. for 1 h, and then NaN₃ (1.59 g, 2.5 mmol)was added at 0° C. under N₂ atmosphere.

The mixture was stirred at 20° C. for 2 h. The reaction was quenchedwith water at the same temperature, extracted with EA (2×20 mL). Thecombined organic layer was washed with brine, dried over Na₂SO₄ andfiltered. The filtrate was concentrated to dryness under reducedpressure. The residue, 290-5, (431 mg, crude) was used in next stepwithout further purification.

To a solution of 290-5 (431 mg, crude) in 1,4-dioxane (14 mL) was addedaq. NaOH (114.4 mg, 2 M, 2.9 mmol) at 18° C. The mixture was stirred atthe same temperature for 3 h. The mixture was diluted with EA (20 mL).The organic layer was washed with brine, dried over MgSO₄ andconcentrated at low pressure. The residue was purified via silica gelchromatography (30% EA in PE) to give 290-6 (406.0 mg, 47.9%) as a whitefoam.

To a solution of 290-6 (406.0 mg, 0.68 mmol) in anhydrous DMF (8 mL) wasadded TBSCl (198.7 mg, 1.3 mmol) and imidazole (119.7 mg, 1.8 mmol) at30° C. under N₂ atmosphere. The solution was stirred at this temperaturefor 3 h. The solution was diluted with EA (20 mL) and washed with waterand brine. The organic phase was dried over MgSO₄ and concentrated atlow pressure. The residue was purified via silica gel chromatography(50% EA in PE) to give 290-7 (405.0 mg, 65.28%) as a white solid.

To a solution of 290-7 (405.0 mg, 0.57 mmol) in anhydrous CH₃CN (6 mL)was added 2,4,6-triisopropylbenzene-1-sulfonyl chloride (343.3 mg, 1.13mmol), DMAP (138.5 mg, 1.1 mmol) and TEA (114.7 mg, 1.1 mmol) at 30° C.The mixture was stirred at this temperature for 9 h. NH₃.H₂O (4 mL) wasadded, and the mixture was stirred for 3 h. The mixture was diluted withEA (20 mL) and washed with brine. The organic layer was dried overNa₂SO₄ and concentrated at low pressure. The residue was purified viasilica gel chromatography (50% EA in PE) to give 290-8 (401.0 mg, crude)as a yellow foam.

290-8 (380.0 mg, 0.54 mmol) was dissolved in 80% HCOOH (25 mL), and themixture was stirred at 30° C. for 12 h. The reaction was quenched withMeOH and concentrated under reduced pressure. The residue was purifiedby silica gel chromatography (10% MeOH in DCM) to give 290 (144.0 mg,83.93%) as a white foam. ESI-MS: m/z 319.1 [M+H]⁺; 637.2 [2M+H]⁺.

Example 174 Compound 291

To a solution of 291-1 (30 g, 122.85 mmol) and 1,1-dimethoxycyclopentane(86 g, 660.93 mmol) in DCE (200 mL) was added TsOH.H₂O (2.34 g, 12.29mmol) in one portion at RT. The mixture was heated to 70° C. and stirredfor 14 h. TLC showed that the reaction was completed. The mixture wascooled to R.T. and concentrated under reduced pressure. The residue waspurified by column chromatography (1-10% MeOH in DCM) to give 291-2 (25g, 65.6%) as a white solid.

To a solution of 291-2 (20 g, 64.45 mmol) in anhydrous CH₃CN (200 mL)was added IBX (19.85 g, 70.9 mmol) at RT. The mixture was refluxed for18 h. and then cooled to 0° C. The precipitate was filtered-off, and thefiltrate was concentrated to give crude 291-3 (20 g, 100%) as a yellowsolid.

To a solution of 291-3 (20 g, 64.87 mmol) in 1,4-dioxane (200 mL) wereadded 37% HCHO (20 mL) and 2.0 M NaOH aq. solution (40 mL) at 0° C. Themixture was stirred at R.T. overnight and then neutralized with AcOH topH=7. The solution was treated with NaBH₄ (4.91 g, 129.74 mmol) at 20°C. The mixture was stirred at R.T. for 1.0 h, and the reaction wasquenched with sat. aq. NH₄Cl. The mixture was extracted with EA (3 s 200mL). The organic layer was dried over anhydrous Na₂SO₄ and concentratedat low pressure. The residue was purified by silica gel columnchromatography (1-3% MeOH in DCM) to give 291-4 (9 g, 40.8%) as a whitesolid.

To an ice cold solution of 291-4 (4.5 g, 13.22 mmol) in anhydrous DCM(50 mL) was added pyridine (10.46 g, 132.20 mmol) and Tf₂O (8.21 g,29.08 mmol) dropwise at −30° C. The mixture was stirred at the sametemperature for 1 h. The reaction was quenched with ice water andextracted with EA (3×60 mL). The organic phase was washed with brine,dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified on a silica gel column (PE:EA=5:1) to give 291-5 (5g, 62.57%) as a white solid.

To a stirred solution of 291-5 (5 g, 8.27 mmol) in anhydrous DMF (25 mL)was added NaH (396.96 mg, 9.92 mmol) at 0° C. under N₂. The solution wasstirred at R.T. for 2 h. TLC showed that the reaction was completed. Thesolution of 291-6 was used in next step without any further workup.

To a stirred solution of 291-6 (3.75 g, 8.25 mmol) was added NaN₃ (1.5g, 2.50 g, 38.46 mmol) at 0° C. under N₂ atmosphere. The solution wasstirred at R.T. for 2 h. The reaction was quenched with water andextracted with EA (3×60 mL). The organic layer was washed with brine,dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue, 291-7, was used in the next step without further purification.

To a solution of 291-7 (2.87 g, 8.25 mmol) in anhydrous 1,4-dioxane (30mL) was added NaOH (8.25 mL, 16.50 mmol, 2.0 M in water) at RT. Themixture was stirred at R.T. for 3 h. TLC showed that the reaction wascompleted. The mixture was diluted with EA. The solution was washed withbrine, dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified on the silica gel column (PE:EA=10:1 to 2:1) togive 291-8 (2 g, 66.4%) as a white foam. ¹H-NMR (DMSO, 400 MHz), δ=9.02(s, 1H), 7.40 (d, J=8.0 Hz, 1H), 5.75-5.77 (m, 1H), 5.57 (d, J=3.6 Hz,1H), 5.13-5.16 (m, 1H), 4.90 (d, J=6.4 Hz, 1H), 3.79-3.85 (m, 2H),5.51-5.56 (m, 2H), 3.06-3.09 (m, 1H), 2.05-2.09 (m, 2H), 1.65-1.75 (m,6H).

291-8 (2 g, 5.47 mmol) was dissolved in 80% HCOOH (20 mL) aq. solution,and the mixture was heated to 60° C. for 2 h. The mixture was evaporatedat low pressure. The residue was dissolved in MeOH, and the pH wasadjusted to 7-8 with NH₃.H₂O. The mixture was stirred for 10 mins, andthen concentrated at low pressure. The residue was purified by silicagel chromatography (DCM:MeOH=20:1) to afford 291-9 (1.4 g, 85.5%) as awhite solid.

To a solution of 291-9 (1.00 g, 3.34 mmol) in DMF (5 mL) was addeddiphenyl carbonate (157.49 mg, 735.20 mol) and NaHCO₃ (28.06 mg, 0.334mmol) at 120° C. The mixture was stirred for 16 h. TLC showed that thereaction was completed. The mixture was cooled to R.T. and concentratedat low pressure. The residue was purified by silica gel chromatography(DCM:MeOH=15:1 to 10:1) to afford 291-10 (600 mg, 63.9%) as a yellowsolid. ¹H-NMR (DMSO, 400 MHz), δ=8.49 (s, 1H), 7.83 (d, J=7.2 Hz, 4H),6.46 (s, 1H), 6.31 (d, J=4.8 Hz, 1H), 5.84 (d, J=6.8 Hz, 1H), 5.27 (d,J=5.6 Hz, 2H), 4.43 (s, 1H), 3.53 (d, J=12.8 Hz, 1H), 3.43 (d, J=13.2Hz, 1H), 3.12 (d, J=11.2 Hz, 1H).

To a solution of 291-10 (2 g, 7.11 mmol) and AgNO₃ (1.81 g, 10.67 mmol)in Py (20 mL) was added DMTrCl (3.61 g, 10.67 mmol) in one portion atRT. The mixture was stirred at R.T. for 12 h. TLC showed that thereaction was completed. The mixture was concentrated at low pressure,and the residue was purified by silica gel chromatography(DCM:MeOH=50:1) to afford 291-11 (3 g, 72.3%) as a white solid.

To a solution of 291-11 (1.5 g, 2.57 mmol) in EtOH (5 mL) was added NaOH(5 mL, 2.0 N) in one portion at RT. The mixture was stirred at R.T. for0.5 h. TLC showed that the reaction was completed. The aqueous phase wasextracted with EA (3×60 mL). The organic phase was washed with brine,dried with anhydrous Na₂SO₄, filtered and concentrated in vacuum toafford 291-12 (1.50 g, 97%) as a yellow solid.

To a solution of 291-12 (1.50 g, 2.49 mmol) in Py (6 mL) was added AC₂O(3 mL) in one portion at RT. The mixture was stirred at R.T. for 12 h.TLC showed that the reaction was completed. The mixture wasconcentrated, and the residue was dissolved in water. The aqueous phasewas extracted with EA (3×60 mL). The combined organic phase was washedwith sat. brine, dried with anhydrous Na₂SO₄, filtered and concentratedin vacuum. The residue was purified by silica gel chromatography(PE:EA=1:1) to afford 291-13 (1.5 g, 87.8%) as a white solid. ¹H-NMR(CDCl₃, 400 MHz), δ=8.10 (s, 1H), 7.29-7.34 (m, 10H), 6.77 (d, J=8.0 Hz,4H), 6.36 (d, J=5.2 Hz, 1H), 5.36 (d, J=3.6 Hz, 1H), 5.44 (t, J=4.0 Hz,1H), 5.32 (d, J=8.0 Hz, 1H), 3.80 (s, 6H), 3.58 (d, J=12.8 Hz, 1H), 3.44(d, J=12.8 Hz, 1H), 3.29 (s, 2H), 2.10 (s, 3H), 1.82 (s, 3H).

To a solution of 291-13 (500 mg, 729.2 mol) in MeCN (10 mL) was addedDMAP (178.17 mg, 1.46 mmol) and TPSCl (430.01 mg, 1.46 mmol) in oneportion at RT. The mixture was stirred at R.T. for 3 h. NH₃/THF (20 mL,sat) was added, and the mixture was stirred for 1 h. The mixture wasdiluted with EA and washed with water. The combined organic phase waswashed with sat. brine, dried with anhydrous Na₂SO₄, filtered andconcentrated in vacuum. The residue was purified by silica gelchromatography (DCM:MeOH=50:1) and then purified by pre-HPLC(CH₃CN/H₂O)to afford 291-14 (260 mg, 49.5%) as a yellow solid. ¹H-NMR (MeOD, 400MHz), δ=7.60 (d, J=7.6 Hz, 1H), 7.46 (d, J=7.6 Hz, 1H), 7.28-7.36 (m,7H), 6.89 (d, J=8.4 Hz, 4H), 6.44 (d, J=4.8 Hz, 1H), 5.56-5.69 (m, 4H),3.80 (s, 6H), 3.54 (d, J=13.2 Hz, 1H), 3.39-3.46 (m, 4H), 2.17 (s, 3H),1.83 (s, 3H).

To a solution of 291-14 (440 mg, 642.6 mol) in NH₃:MeOH (5 mL, 7N) wasstirred at R.T. for 16 h. TLC showed that the reaction was completed.The mixture was concentrated under reduced pressure at 40° C. Theresidue was purified by silica gel chromatography (DCM:MeOH=100:1˜20:1)to afford 291-15 (290 mg, 75.13%) as a white solid. ¹H-NMR (MeOD, 400MHz), δ=7.62 (d, J=7.6 Hz, 1H), 7.43 (d, J=7.6 Hz, 1H), 7.23-7.33 (m,7H), 6.86 (d, J=8.4 Hz, 4H), 6.31 (d, J=4.8 Hz, 1H), 5.54 (d, J=7.2 Hz,1H), 4.34 (t, J=4.4 Hz, 1H), 4.27 (d, J=4.0 Hz, 1H), 3.78 (s, 6H), 3.69(d, J=12.8 Hz, 1H), 3.46 (d, J=12.8 Hz, 1H), 3.41 (s, 2H).

A solution of 291-15 (150 mg, 249.74 μmol) in 80% CH₃COOH (5 mL) wasstirred at 60° C. for 2 h. TLC showed that the reaction was completed.The mixture was treated with MeOH and concentrated under reducedpressure at 60° C. The residue was purified by silica gel chromatography(1-10% MeOH in DCM) to afford 291 (65 mg, 78.5%) as a white solid.ESI-MS: m/z 299.1 [M+H]⁺.

Example 175 Compound 293

To a solution of 293-1 (12 g, 45.42 mmol) in pyridine (100 mL) was addedDMTrCl (16.16 g, 47.69 mmol) in portions at 0° C. over a period of 30mins under N₂. The mixture was warmed to 25° C. and stirred for 16 h.LCMS and TLC (DCM:MeOH=20:1) showed that the starting material wasconsumed. The reaction was quenched with MeOH (10 mL) and thenconcentrated in vacuum. The residue was purified by silica gelchromatography (100-200 mesh silica gel, PE:EA=1:1) to give pureDMTr-293-1 (20 g, 77.7%) as a white solid.

To a solution of DMTr-293-1 (30.00 g, 52.95 mmol) and TBSCl (19.95 g,132.38 mmol, 2.50 eq.) in DCM (200 mL) was added imidazole (9.00 g,132.20 mmol, 2.50 eq.) in portions at 0° C. The temperature wasmaintained below 5° C. The mixture was warmed to 25° C., and stirred for16 h. TLC (PE:EA=1:1) showed that the starting material was consumed.The reaction was quenched by ice and then extracted with DCM (2×50 mL).The combined organic phase was washed with brine (50 mL), dried overanhydrous Na₂SO₄, filtered and concentrated at low pressure. The residuewas purified by chromatography to give the pure product (30.00 g, 83.2%)as a white solid.

The product from the previous step (30.00 g, 44.07 mmol) was dissolvedin 80% AcOH aqueous (300 mL), and the mixture was stirred at 25° C. for16 h. TLC (DCM:MeOH=10:1) showed that the reaction was completed. Thereaction was quenched with sat. aq. NaHCO₃ (100 mL) and then extractedwith EA (3×100 mL). The organic phase was washed with brine, dried overanhydrous Na₂SO₄ and concentrated under reduced pressure. The residuewas purified by a silica gel column (DCM:MeOH=50:1˜20:1) to give 293-2(15.5 g, 92.9%) as a white solid.

To a solution of 293-2 (8.00 g, 21.14 mmol) in MeCN (80 mL) was addedIBX (6.51 g, 23.25 mmol, 1.10 eq.) at 25° C. under N₂. The mixture washeated to 81° C. for 1 h. LCMS showed that the starting material wasconsumed. The mixture was filtered, and the filtrates were concentratedin vacuum. The aldehyde residue (7.50 g, 19.92 mmol) was used in nextstep without further purification.

To a solution of the aldehyde from the previous step (7.5 g, 19.9 mmol)and aq. formaldehyde (7.85 mL) in dioxane (80 mL) was added 2.0 N aq.NaOH (19.5 mL) in one portion at 25° C. The mixture was stirred at 25°C. for 16 h. TLC showed that the reaction was completed. The mixture wascooled to 0° C. and then neutralized with AcOH to pH=7. The solutionwere treated with NaBH₄ (4.52 g, 119.52 mmol) at 0° C. The mixture wasstirred at 25° C. for 30 mins, and the reaction was quenched with sat.aq. NH₄Cl (100 mL). The mixture was extracted with EA (2×100 mL). Theorganic phase was dried over anhydrous Na₂SO₄, filtered and concentratedin vacuum. The residue was purified by silica gel chromatography(100-200 mesh silica gel, DCM:MeOH=20:1 to 10:1) to afford 293-3 (4.0 g,49.2%) as a white solid.

To a solution of 293-3 (4.00 g, 9.79 mmol) in pyridine (20 mL) was addeda solution of MMTrCl (3.48 g, 10.28 mmol) in DCM (20 mL) dropwise at 0°C. over a period of 15 mins. The temperature was maintained below 5° C.The mixture was warmed to 25° C. and stirred at 2 5° C. for 16 h. TLC(DCM:MeOH=10:1) showed that the starting material was consumed. Thereaction was quenched by MeOH (5 mL) and concentrated in vacuum. Theresidue was purified by column (DCM:MeOH=50:1) to give a pureintermediate (5.00 g, 71.85%) as a white solid.

To a solution of the above intermediate (5.00 g, 7.03 mmol) and AgNO₃(2.39 g, 14.06 mmol, 2.00 eq.) in pyridine (40 mL) was added dropwiseTBDPSCl (2.90 g, 10.55 mmol) at 0° C. over a period of 10 mins. Themixture was warmed to 25° C. and stirred for 16 h. TLC (PE:EA=1:1)showed that the starting material was consumed. The reaction wasquenched by ice and then extracted with EA (3×100 mL). The combinedorganic phase was washed with sat. brine (2×50 mL), dried over anhydrousNa₂SO₄, filtered and concentrated in vacuum. The residue (5.00 g, crude)was dissolved in 80% aq. AcOH (50 mL), and the mixture was stirred at25° C. for 2 h. TLC (PE:EA=2:1) showed that the reaction was completed.The reaction was quenched by MeOH (5 mL) and then extracted with DCM(3×100 mL). The organic phase was washed with brine, dried overanhydrous MgSO₄ and concentrated at low pressure. The residue waspurified by a silica gel column (PE:EA=5:1 to 2:1) to give 293-4 (2.50g, 55%) as a yellow solid.

To a solution of 293-4 (400 mg, 618.36 mol) in DCM (4 mL) was added DMP(393.4 mg, 927.54 mol, 1.50 eq.) in one portion at 0° C. under N₂. Themixture was stirred at 25° C. for 2 h. TLC (PE:EA=2:1) showed that thereaction was completed. The mixture was cooled to 0° C. and quenchedwith sat. aq. Na₂SO₃ (5 mL) and aq. NaHCO₃ (5 mL). The aqueous layer wasextracted with DCM (3×10 mL). The combined organic phase was washed withsat. brine (10 mL), dried over anhydrous Na₂SO₄, filtered andconcentrated in vacuum. The residue was purified by silica gelchromatography (100-200 mesh silica gel, PE:EA=3:1) to afford 293-5(300.00 mg, 75.24%) as a white solid.

To a solution of 293-5 (500 mg, 775.37 mol) in pyridine (5 mL) was addedhydroxylamine hydrochloride (215.5 mg, 3.10 mmol, 4.00 eq.) in oneportion at 0° C. under N₂. The mixture was stirred at 0° C. for 30 mins,and then warmed to 25° C. and stirred for 4 h. LCMS showed that thereaction was completed. The mixture was concentrated in vacuum. Theresidue was purified by silica gel chromatography (100-200 mesh silicagel, PE:EA=2:1) to afford the oxime (450 mg, 87.95% yield) as a lightyellow solid.

To a solution of this oxime (450.00 mg, 681.95 mol) in DCM (5 mL) wasadded TEA (208.0 mg, 2.06 mmol) and MsCl (156.0 mg, 1.36 mmol) in oneportion at 0° C. The mixture was stirred at 25° C. for 4 h. TLC(PE:EA=2:1) showed that the reaction was completed. The reaction wasquenched by sat. aq. NaHCO₃ (5 mL), and the aqueous phases wereextracted with DCM (2×20 mL). The combined organic phase was washed withsat. brine (10 mL), dried with anhydrous Na₂SO₄, filtered andconcentrated in vacuum. The residue was purified by TLC (PE:EA=2:1) toafford 293-6 (400 mg, 91.4%) as a light yellow solid.

To a solution of 293-6 (450.0 mg, 701.10 μmol), DMAP (171.3 mg, 1.40mmol) and TEA (212.8 mg, 2.10 mmol) in MeCN (5 mL) was added2,4,6-triisopropylbenzene-1-sulfonyl chloride (424.7 mg, 1.40 mmol) inone portion at 0° C. The mixture was stirred at 25° C. for 1 h. TLC(PE:EA=2:1) showed that the reaction was completed. The reaction wasquenched by sat. aq. NaHCO₃ (5 mL) and extracted with EA (2×15 mL). Thecombined organic phase was washed with sat. brine (10 mL), dried withanhydrous Na₂SO₄, filtered and concentrated in vacuum. The residue(580.00 mg, 638.59 μmol) was dissolved in MeCN (5 mL). The solution wastreated with NH₃.H₂O (10 mL) in one portion at 25° C. The mixture wasstirred at 25° C. 16 h. TLC (PE:EA=1:1) showed the reaction wascompleted. The mixture was extracted with EA (3×10 mL). The combinedorganic phase was washed with sat. brine (10 mL), dried with anhydrousNa₂SO₄, filtered and concentrated in vacuum. The residue was purified bysilica gel chromatography (100-200 mesh silica gel, DCM:MeOH=40:1 to25:1) to afford 293-7 (350.00 mg, 85.5%) as a light yellow solid.

To a solution of 293-7 (350.0 mg, 546.13 μmol) in MeOH (10 mL) was addedNH₄F (405 mg, 10.9 mmol) in one portion at 25° C. The mixture was heatedto 65° C. and stirred for 2 h. TLC (EA:MeOH=8:1) showed that thereaction was completed. The mixture was cooled to 25° C. andconcentrated under reduced pressure at 40° C. The residue was purifiedby silica gel chromatography (100-200 mesh silica gel, EA:MeOH=20:1 to10:1) to afford 293 as a white solid. ¹H NMR (400 MHz, DMSO-d₆), δ=7.59(d, J=7.28 Hz, 1H), 7.49 (br. s., 2H), 7.25 (br. s., 1H), 6.29 (br. s.,1H), 6.01 (br. s., 1H), 5.82 (d, J=7.53 Hz, 1H), 4.60 (br. s., 1H), 3.88(br. s., 2H); ¹⁹F NMR (376 MHz, DMSO-d₆) d ppm −116.61 (br. s., 1F)−115.98 (br. s., 1F).

Example 176 Compound 294

To a solution of K₂CO₃ (967.5 mg, 7.0 mmol) and TsN₃ (552.2 mg, 2.80mmol) in MeCN (10 mL) was added 1-dimethoxyphosphorylpropan-2-one (465.1mg, 2.80 mmol) in one portion at 25° C. under N₂. The mixture wasstirred at 25° C. for 2 H. A solution of 293-5 (900.0 mg, 1.40 mmol,1.00 eq.) in MeOH (10 mL) was added in one portion at 25° C. under N₂.The mixture was stirred at 25° C. for 12 h. TLC (PE:EA=2:1) showed thatthe reaction was completed. The mixture was poured into water (10 mL)and extracted with EA (2×50 mL). The combined organic phase was washedwith saturated brine (10 mL), dried with anhydrous Na₂SO₄, filtered andconcentrated in vacuum. The residue was purified by silica gelchromatography (100-200 mesh silica gel, PE:EA=5:1 to 2:1) to afford294-1 (800 mg, 98.2%) as an off-white solid.

To a solution of 294-1 (500 mg, 780.20 μmol), DMAP (190.6 mg, 1.56 mmol)and TEA (236.9 mg, 2.34 mmol) in MeCN (5 mL), was added2,4,6-triisopropylbenzene-1-sulfonyl chloride (472.8 mg, 1.56 mmol) inone portion at 0° C. under N₂. The mixture was stirred at 0° C. for 30mins, then warmed to 25° C. and stirred for 2 h. TLC (PE:EA=2:1) showedthat the reaction was completed. The reaction was quenched by water (5mL) and extracted with EA (2×10 mL). The combined organic phase waswashed with aq. HCl (1 mL, 0.5 M), dried with anhydrous Na₂SO₄, filteredand concentrated in vacuum. The residue (650.0 mg, 91.83%) was obtainedas a light yellow gum, which was used in next step without furtherpurification.

To a solution of the residue from the previous step (650 mg, 716.4 μmol)in MeCN (5 mL) was added NH₃.H₂O (5 mL) in one portion at 25° C., andthe mixture was stirred at 25° C. for 16 h. TLC (DCM:MeOH=20:1) showedthat the reaction was completed. The mixture was extracted with EA (2×20mL). The combined organic phase was washed with brine (10 mL), driedwith anhydrous Na₂SO₄, filtered and concentrated in vacuum. The residuewas purified by silica gel chromatography (100-200 mesh silica gel,PE:EA=1:1) to afford 294-2 (350 mg, 76.35%) as an off-white solid.

A mixture of 294-2 (350.0 mg, 546.98 μmol) and NH₄F (405.0 mg, 10.93mmol) in MeOH (5 mL) was heated to 65° C. and stirred for 2 h. LCMS andTLC (EA:MeOH=10:1) showed that the reaction was completed. The mixturewas cooled to 25° C. and filtered, and the filtrate was concentrated invacuum. The residue was purified by silica gel chromatography (300-400mesh silica gel, EA:MeOH=20:1 to 10:1) to afford 294 (102 mg, 64.93%) asa white solid. ¹H-NMR (400 MHz, METHANOL-d₄), δ=7.73 (d, J=7.28 Hz, 1H),6.31-6.42 (m, 1H), 5.95 (d, J=7.53 Hz, 1H), 4.47 (t, J=13.55 Hz, 1H),3.92 (d, J=12.55 Hz, 1H), 3.73-3.80 (m, 1H) 3.25 (s, 1H); ¹⁹F NMR (376MHz, METHANOL-d4), δ=−115.52-−112.60 (m, 1F).

Example 177 Compound 295

To a solution of 295-1 (20 g, 66.8 mmol) in anhydrous pyridine (180 mL)was added BzCl (30.9 g, 220.3 mmol) at 0° C. under N₂. The mixture wasstirred at 25° C. for 12 h. The mixture was diluted with EA and washedwith sat. aq. NaHCO₃. The organic layer was dried over anhydrous Na₂SO₄and filtered, and the filtrate was concentrated to dryness. The residuewas purified by silica gel column chromatography (30% EA in PE) to give295-2 (34.6 g, 90%) as a white solid.

295-2 (33 g, 57.3 mmol) was dissolved in 90% CH₃COOH (360 mL) and heatedto 115° C. The mixture was stirred at 115° C. for 12 h. The solvent wasremoved, and the residue was diluted with EA. The mixture was washedwith sat. aq. NaHCO₃ and brine. The organic layer was dried overanhydrous Na₂SO₄ and filtered. The filtrate was concentrated to give295-3 (26 g, crude) as a white solid.

295-3 (21 g, 44.5 mmol) was dissolved in a solution (400 mL, 10M) of NH₃in MeOH. The mixture was stirred at 25° C. for 12 h. The mixture wasconcentrated to give a residue, which was purified by silica gel columnchromatography (5% MeOH in DCM) to give 295-4 (9.4 g, 80.4%) as a whitesolid. ¹H-NMR (CD₃OD, 400 MHz) δ=7.90-7.80 (m, 1H), 6.18-6.09 (m, 1H),5.71 (d, J=8.2 Hz, 1H), 4.26 (dt, J=8.2, 12.0 Hz, 1H), 3.98-3.84 (m,2H), 3.76 (dd, J=2.8, 12.5 Hz, 1H), 3.33 (s, 1H).

To a solution of 295-4 (9 g, 34.1 mmol) in anhydrous pyridine (60 mL)was added TBSCl (7.7 g, 51.1 mmol) at 25° C. under N₂. The solution wasstirred at 50° C. for 12 h. The mixture was concentrated to drynessunder reduced pressure. The residue was dissolved in EA. The mixture waswashed with sat. aq. NaHCO₃ and brine. The organic layer was dried overMgSO₄ and concentrated to dryness under reduced pressure. The residuewas purified on a silica gel column (20% EA in PE) to give 295-5 (11 g,85.5%) as a white solid.

To a solution of 295-5 (10.2 g, 27 mmol) in CH₂Cl₂ (100 mL) was addedAgNO₃ (9.2 g, 53.9 mmol), collidine (13.1 g, 107.8 mmol) and MMTrCl (10g, 32.3 mmol) at 25° C. under N₂. The solution was stirred at 25° C. for12 h. The reaction was quenched with MeOH, and the mixture was filtratedon celite. The filtrate was diluted with CH₂Cl₂ and H₂O. The organiclayer was separated, and the aqueous phase was extracted with CH₂Cl₂.The combine organic layer was washed with brine, dried over anhydrousMgSO₄ and filtered. The filtrate was concentrated to dryness underreduced pressure. The residue was purified by silica gel chromatography(25% EA in PE) to give 295-6 (15 g, 85.6%) as a white solid.

295-6 (10.5 g, 16.1 mmol) was dissolved in a solution of TBAF in THF(1M, 60 mL) at 25° C. The mixture was stirred at 25° C. for 4 h. Themixture was extracted with EA, and the combined layer was washed withwater and brine. The organic layer was dried over Na₂SO₄ and filtered.The filtrate was concentrated to give the crude product, which waspurified by silica gel column chromatography (30% EA in PE) to give295-7 (8.1 g, 93.6%) as a white foam.

To a solution of 295-7 (17.0 g, 31.7 mmol) in CH₃CN (150 mL) was addedIBX (9.7 g, 34.9 mmol) at 25° C. The mixture was heated to 100° C., andthe mixture was stirred at 100° C. for 1 h. The mixture was cooled to25° C. The mixture was filtered, and the filter cake was washed withMeCN. The filtrate was concentrated under reduce pressure to give aresidue (16 g, crude) as a yellow solid. The residue (16 g, crude) wasdissolved in 1,4-dioxane (150 mL), and the solution was treated with 37%aq. formaldehyde (18.5 g, 227.5 mmol) and aq. NaOH (2 M, 30 mL) at 25°C. The mixture was stirred at 25° C. for 12 h. EtOH (30 mL) and NaBH₄(10 g, 265.7 mmol) were added at 0° C. After stirring for 1 h at 25° C.,the reaction was quenched with sat. aq. NH₄Cl at 0° C. The mixture wasdiluted with EA. The organic phase was separated, and the aqueous phasewas extracted with EA. The combined organic phase was washed with brineand dried over anhydrous Na₂SO₄. The organic layer was concentrated invacuum to give a residue, which was purified by silica gelchromatography (2% MeOH in DCM) to afford 295-8 (8.1 g, 53.1%) as awhite solid. ¹H-NMR (400 MHz, DMSO-d₆) δ=11.52 (s, 1H), 7.57 (d, J=8.2Hz, 1H), 7.46-7.22 (m, 13H), 6.90 (d, J=8.8 Hz, 2H), 6.30 (t, J=8.0 Hz,1H), 5.61 (d, J=8.2 Hz, 1H), 5.06 (t, J=5.5 Hz, 1H), 4.92-4.86 (m, 1H),4.61-4.51 (m, 1H), 3.83 (dd, J=5.1, 12.1 Hz, 1H), 3.74 (s, 3H).

To an ice cooled solution of 295-8 (2.5 g, 4.4 mmol) in anhydrous CH₂Cl₂(35 mL) was added pyridine (3.5 g, 44.1 mmol) and Tf₂O (3.7 g, 13.2mmol) dropwise. The mixture was stirred at 0° C. for 40 mins. Thereaction was quenched with ice water and stirred for 10 mins. Themixture was extracted with CH₂Cl₂. The organic layer was washed withbrine and dried over MgSO₄. The organic layer was concentrated to give aresidue, which was purified on the silica gel column (15% EA in PE) togive 295-9 (2.6 g, 71%) as a yellow foam.

To a stirred solution of 295-9 (1.8 g, 2.2 mmol) in anhydrous DMF (25mL) was added NaH (107 mg, 2.7 mmol) at 0° C. under N₂. The solution wasstirred at 25° C. for 1 h. TLC (PE: EA=1:1) showed the reaction wascomplete. To the solution was added NaI (3.1 g, 20.6 mmol) at 25° C. Themixture was stirred at 25° C. for 3 h. TLC (PE: EA=1:1) showed thereaction was complete. The mixture was diluted with water and extractedwith EA. The organic layer was dried over anhydrous Na₂SO₄ and filtered.The filtrate was concentrated at low pressure to give 295-10 (1.4 g,crude) as a yellow solid.

295-10 (1.4 g, crude) was dissolved in 1,4-dioxane (25 mL), and themixture was treated with aq. NaOH (2 M, 2.7 mL) at 0° C. The solutionwas stirred for 4 h at 25° C. The reaction was quenched with sat. aq.NH₄Cl and extracted with EA. The organic layer was washed with brine.The organic layer was dried over anhydrous Na₂SO₄ and filtered. Thefiltrate was concentrated to give the crude product, which was purifiedby silica gel column chromatography (40% EA in PE) to give 295-11 (1.4g, 94.9%).

To a solution of 295-11 (1.45 g, 2.1 mmol) in EtOH (10 mL) was addedEt₃N (434 mg, 4.3 mmol) and Pd/C (101 mg, 88.7 mol). The mixture wasstirred under H₂ (15 psi) for 12 h at 25° C. The suspension wasfiltered, and the filtrate was concentrated at low pressure. The residuewas purified on silica gel column (1% MeOH in DCM) to give 295-12 (1.2g, 97.6%) as a yellow solid.

To a solution of 295-12 (930 mg, 1.7 mmol) in anhydrous DMF (10 mL) wasadded imidazole (287 mg, 4.2 mmol) and TBSCl (636 mg, 4.2 mmol) at 25°C. under N₂. The solution was stirred at 25° C. for 5 h. The mixture wasconcentrated to dryness under reduced pressure, and the residue wasdissolved in EA. The mixture was washed with sat. aq. NH₄Cl and brine.The organic layer was dried over MgSO₄ and filtered. The filtrate wasconcentrated to dryness under reduced pressure. The residue was purifiedon silica gel column (15% EA in PE) to give 295-13 (968 mg, 86.2%) as awhite solid.

To a stirred solution of 295-13 (568 mg, 854.4 mol) in anhydrous CH₃CN(8 mL) was added DMAP (209 mg, 1.7 mmol), TPSCl (504 mg, 1.7 mmol) andTEA (173 mg, 1.7 mmol) at 25° C. The mixture was stirred at 25° C. for12 h. NH₃.H₂O (10 mL) was added, and the mixture was stirred for 3 h.The mixture was extracted with EA and washed with sat. aq. NH₄Cl andbrine. The organic layer was dried over Na₂SO₄ and filtered.

The filtrate was concentrated to give a residue, which was purified on asilica gel column (3% MeOH in DCM) to give 295-14 (480 mg, 84.6%) as ayellow foam. ¹H-NMR (400 MHz, CDCl₃) δ=7.65-7.40 (m, 13H), 6.97 (d,J=8.8 Hz, 2H), 6.44 (dd, J=6.4, 9.5 Hz, 1H), 5.71 (d, J=7.3 Hz, 1H),4.76 (dd, J=9.0, 14.4 Hz, 1H), 4.29 (q, J=7.1 Hz, 1H), 3.92-3.92 (m,1H), 3.95 (s, 3H), 3.60 (d, J=11.2 Hz, 1H), 3.44 (d, J=11.0 Hz, 1H),1.66-1.55 (m, 3H), 0.95 (s, 9H), 0.08 (s, 3H), 0.00 (s, 3H).

295-14 (501 mg, 753.2 μmol) was dissolved in 80% HCOOH (20 mL), and themixture was stirred at 25° C. for 4 h. The solvent was removed at lowpressure, and the residue was purified on a silica gel column (6% MeOHin DCM) to give 295 (151 mg, 71.8%) as a white solid. ESI-MS: m/z 278.11[M+H]⁺, 555.18 [2M+H]+.

Example 178 Compound 298

To a solution of 298-1 (120 g, 0.26 mol) in anhydrous MeCN (2 L) wasadded IBX (109 g, 0.39 mol). The mixture was heated to reflux andstirred for 18 h. The mixture was cooled to 0° C. and filtered. Thefiltrate was concentrated under vacuum to give 298-2 (142 g) as a brownoil, which was used without purification for the next step.

To a solution of 298-2 (142 g) in anhydrous THF (1.5 L) was addedvinylmagnesium bromide (830 mL, 0.83 mol, 1 N) dropwise at −78° C., andthe mixture was stirred at −78° C. for 2 h. The reaction was quenched bysat. aq. NH₄Cl (2 L) at 0° C. THF was removed under vacuum, and theresidue was diluted with EtOAc. The solution was washed with brine,dried over anhydrous Na₂SO₄, filtered and concentrated to give a lightbrown oil.

To the light brown oil in anhydrous DCM (2.5 L) was added DMAP (63.5 g,0.52 mol), Et₃N (79 g, 0.78 mol) and BzCl (110 g, 0.78 mol) at 0° C.,and the mixture stirred overnight at RT. The mixture was diluted withDCM (2 L) and washed with sat. aq. NaHCO₃ (3 L) and brine (1.5 L). Theorganic phase was dried over anhydrous Na₂SO₄, filtered and evaporatedto dryness under reduced pressure. The residue was purified by silicagel column (PE:EA=20:1˜10:1) to give 298-3 (112.7 g, 72.3%) as a yellowoil.

A stirring mixture of uracil (36.25 g, 323.7 mmol) andN,O-bis(trimethylsilyl) acetamide (131.69 g, 647.4 mmol) in anhydrousMeCN (180 mL) was heated to reflux for 2 h, then cooled to RT. Asolution of 298-3 (95.9 g, 161.85 mmol) in anhydrous MeCN (500 mL) wasadded, followed by treatment with SnCl₄ (168.66 g, 647.4 mmol) dropwiseat 0° C. The mixture was heated to reflux and stirred for 2 h. Thereaction was quenched with sat. aq. NaHCO₃ (3 L), and extracted withEtOAc (3×1 L). The organic phase was washed with brine (500 mL), driedover anhydrous Na₂SO₄, filtered and evaporated to dryness under reducedpressure. The residue was purified by a silica gel column(PE:EA=20:1˜10:1) to give 298-4 (33 g, 35%) as a light yellow oil.

298-4 (33 g, 56.65 mmol) was dissolved in NH₃:MeOH (800 mL, 7 N), andthe mixture was stirred at R.T. overnight. The solvent was removed underreduced pressure, and the residue was purified by a column (1% MeOH inDCM) to give 298-5 (12.6 g, 82.4%) as a light yellow foam.

To a solution of 298-5 (2.57 g, 8.76 mmol) in DMF (20 mL) was addedAgNO₃ (8.93 g, 52.56 mmol) and imidazole (3.58 g, 52.56 mmol), thenTBSCl (5.28 g, 35.04 mmol) was added in one portion at 0° C. under N₂.The mixture was stirred at 25° C. for 12 h. TLC showed that the reactionwas completed. The residue was poured into ice:water (w:w=1:1) (30 mL).The aqueous phase was extracted with EA (3×100 mL). The combined organicphase was washed with sat. brine (3×20 mL), dried with anhydrous Na₂SO₄,filtered and concentrated in vacuum. The residue was purified by silicagel chromatography (column height: 250 mm, diameter: 100 mm, 100-200mesh silica gel, PE:EA=3:1 to 2:1) to afford 298-6 (3.68 g, 80.51%) as ayellow solid.

To a solution of 298-6 (3.48 g, 6.67 mmol) and AgNO₃ (3.40 g, 20.01mmol) in pyridine (30 mL) was added(chloro(4-methoxyphenyl)methylene)dibenzene (4.12 g, 13.34 mmol) in oneportion at 25° C. under N₂. The mixture was stirred at 25° C. for 16 h.TLC showed that the reaction was completed. The mixture was diluted withEA and filtered. The filtrate was washed with brine and separated. Theorganic layer was concentrated to dryness. The residue was purified bysilica gel chromatography (column height: 250 mm, diameter: 100 mm,100-200 mesh silica gel, PE:EA=10:1 to 5:1) to afford 298-7 (4.40 g,83.07%) as a yellow foam.

To a solution of 298-7 (4.30 g, 5.41 mmol) in MeOH (100 mL) was addedNH₄F (801.55 mg, 21.64 mmol) in one portion at 25° C. The mixture washeated to 68° C. and stirred for 4 h. LCMS trace showed that thereaction was completed. The mixture was cooled to 25° C. andconcentrated under reduced pressure. The residue was purified by silicagel chromatography (column height: 250 mm, diameter: 100 mm, 100-200mesh silica gel, DCM:MeOH:NH₃.H₂O=30:1:0.05 to 10:1:0.05) to afford298-8 (3.00 g, 98.04%) as a white solid.

To a solution of 298-8 (3.00 g, 5.30 mmol) in DMF (30 mL) was added NaH(848 mg, 21.20 mmol) in one portion at 0° C. under N₂. The mixture wasstirred at 0° C. for 30 mins. BnBr (3.63 g, 21.20 mmol) was added at 0°C., and the mixture was stirred for 16 h at 25° C. TLC showed that thereaction was completed. The mixture was poured into ice-water (w:w=1:1)(30 mL). The aqueous phase was extracted with EA (3×50 mL). The combinedorganic phase was washed with sat. brine (3×20 mL), dried with anhydrousNa₂SO₄, filtered and concentrated in vacuum. The residue was purified bysilica gel chromatography (column height: 250 mm, diameter: 100 mm,200-300 mesh silica gel, PE:EA=20:1 to 10:1) to afford 298-9 (670 mg,15.1%).

Ozone was bubbled into a solution of 298-9 (500 mg, 598.10 μmol) in DCM(8 mL) and MeOH (8 mL) at −78° C. for 20 mins. After excess O₃ waspurged by O₂, NaBH₄ (113.13 mg, 2.99 mmol) was added at 0° C. Themixture was stirred at 25° C. for 20 mins. TLC showed that the startingmaterial was consumed. The mixture was concentrated to give the crudeproduct, which was purified by silica gel chromatography (PE:EA=5:1) togive 298-10 (167.00 mg, 33.24%) as a yellow solid.

To a solution of 298-10 (216.70 mg, 257.99 μmol) and DMAP (63.04 mg,515.98 μmol) in DCM (2 mL) was added MsCl (44.33 mg, 386.98 μmol) in oneportion at 0° C. under N₂. The mixture was stirred at 0° C. for 1 h andthen warmed to 25° C. and stirred for 1 h. LCMS showed that the reactionwas completed. The residue was poured into ice-water (w:w=1:1) (10 mL),and extracted with EA (3×20 mL). The combined organic phase was washedwith sat. brine (3×10 mL), dried with anhydrous Na₂SO₄, filtered andconcentrated in vacuum. The residue was purified by silica gelchromatography (column height: 250 mm, diameter: 100 mm, 100-200 meshsilica gel, PE:EA=10:1 to 5:1) to afford a mesylate intermediate (167.00mg, 70.51%) as a yellow foam.

The mesylated intermediate (167 mg) was dissolved in TBAF:THF (10 mL,1N) and the mixture was heated to reflux for 12 h. The mixture wasslowly cooled to 25° C., and quenched with sat. NH₄Cl solution. Thesolution was extracted with EA. The combined organic layers were washedwith brine, dried over anhydrous Na₂SO₄ and concentrated to dryness. Theresidue was purified by column chromatography (EA:PE=5:1-2:1) to give298-11 (80 mg, 43.8%).

298-11 (80.00 mg, 0.087 mmol) was dissolved in 80% AcOH (5 mL) solution,and stirred at 45° C. for 1.0 h. The reaction was quenched with sat.Na₂HCO₃ solution and extracted with EA (3×10 mL). The combined organiclayers were washed with brine, dried over anhydrous Na₂SO₄ andconcentrated to dryness. The residue was purified by columnchromatography to give 298-12 (38 mg, 60%) as a white foam solid.ESI-MS: m/z 570.4 [M+H]⁺.

To a solution of 298-12 (113.8 mg, 0.2 mmol) in DCM (0.5 mL) was addedBCl₃/DCM (1.0 N) (1 mL) at −78° C., and the mixture was stirred at −78°C. for 30 mins. The reaction was quenched with MeOH and concentrated todryness at low pressure. The residue was purified by prep-HPLC withNH₃.H₂O buffer to give 298 (26 mg, 44%) as a white solid.

Example 179 Compound 302

To a mixture of 302-1 (2.00 g, 3.5 mmol) in pyridine (10 mL) and DCM (10mL) was added BzCl (496 mg, 3.5 mmol) dropwise at 0° C. under N₂. Themixture was stirred at 0° C. for 30 mins, and then stirred at 25° C. for6.5 h. The reaction was quenched with sat. aq. NaHCO₃ (80 mL). Themixture was extracted with EA (2×100 mL). The organic phase was washedwith brine (80 mL), dried over anhydrous Na₂SO₄ and filtered. Thefiltrate was concentrated under reduced pressure. The residue waspurified by silica gel chromatography (30% EA in PE) to afford 302-2(1.28 g, 54%) as a white solid.

To a mixture of 302-2 (680 mg, 1.0 mmol) in DMF (5 mL) was addedimidazole (412 mg, 6.1 mmol), AgNO₃ (514 mg, 3.0 mmol) and TBDPSCl (832mg, 3.0 mmol) at 25° C. under N₂. The mixture was stirred at 25° C. for12 h. The reaction was quenched with sat. aq. NaHCO₃ (30 mL), and thenextracted with EA (2×30 mL). The combined organic phase was washed withbrine (2×20 mL), dried over anhydrous Na₂SO₄, filtered and concentratedunder reduced pressure. The residue was purified by silica gelchromatography (25% EA in PE) to afford 302-3 (750 mg, 82%) as a whitesolid.

302-3 (660 mg, 0.7 mmol) was dissolved in NH₃:MeOH (15 mL). The mixturewas stirred at 25° C. for 36 h in sealed tube, and then concentratedunder reduced pressure. The residue was purified by silica gelchromatography (30% EA in PE) to afford 302-4 (430 mg, 73%) as a whitesolid. ¹H-NMR (CDCl₃, 400 MHz) δ=9.05 (s, 1H), 7.81-7.10 (m, 21H), 6.81(d, J=9.2 Hz, 2H), 6.42 (m, 1H), 6.20 (m, 1H), 4.13-4.07 (m, 2H),3.78-3.60 (m, 5H), 2.55 (s, 1H), 0.90-0.74 (m, 9H).

To a mixture of 302-4 (280 mg, 0.3 mmol) in DCM (3.5 mL) was addedDess-Martin (295 mg, 0.7 mmol) in one portion at 0° C. under N₂. Themixture was stirred at 25° C. for 3.5 h. The reaction was quenched withsat. aq. NaHCO₃ and sat. aq. Na₂S₂O₃. (v:v=1:1, 30 mL). The mixture wasextracted with EA (2×20 mL). The combined organic phase was washed withbrine (30 mL), dried over anhydrous Na₂SO₄ and filtered. The filtratewas concentrated in vacuum to afford 302-5 (260 mg, crude) as a yellowsolid, which was used in the next step without further purification.

To a stirred solution of Methyl-triphenyl-phosphonium bromide (359 mg,1.0 mmol) in anhydrous THF (1 mL) was added KOBu-t (1 mL, 1.0 mmol, 1 Min THF) dropwise at 0° C. The mixture was stirred at 25° C. for 1 h. Asolution of 302-5 (260 mg, 0.3 mmol) in anhydrous THF (1 mL) was addedat 0° C. The mixture was stirred at 25° C. for 16 h. The reaction wasquenched with sat. aq. NH₄Cl (20 mL) and extracted with EA (30 mL). Theorganic layer was washed with brine (20 mL), dried over MgSO₄, filteredand evaporated to give a light white solid, which was purified by columnchromatography (10% EA in PE) to give 302-6 (131 mg, 50%) as a yellowsolid. ¹H-NMR (CDCl₃, 400 MHz) δ =8.40 (s, 1H), 7.55-7.21 (m, 21H), 7.10(dd, J=1.8, 8.2 Hz, 1H), 6.84 (d, J=8.8 Hz, 2H), 6.37 (dd, J=11.0, 17.4Hz, 1H), 6.09 (dd, J=7.2, 8.9 Hz, 1H), 5.59-5.43 (m, 2H), 5.10-4.92 (m,2H), 3.85-3.78 (s, 3H), 3.78-3.73 (m, 1H), 3.56 (d, J=11.5 Hz, 1H),0.99-0.77 (s, 9H).

To a solution of 302-6 (1.50 g, 1.9 mmol) in THF (5 mL) was added 9-BBN(0.5 M, 22.5 mL) at 27° C. under N₂. The mixture was heated to 70° C. bymicrowave and stirred for 0.5 h. Sat. aq. NaHCO₃ (15 mL) and H₂O₂ (7.5mL) were added at 0° C. The mixture was stirred vigorously at 27° C. for1.5 h. The reaction was quenched with sat. aq. Na₂S₂O₃ (60 mL). Themixture was extracted with EA (2×50 mL). The organic layer was washedwith brine (80 mL), dried over MgSO₄, filtered and evaporated todryness. The residue was purified by silica gel chromatography (30% EAin PE) to afford 302-7 (930 mg, 61%) as a white solid.

To a solution of 302-7 (1.24 g, 1.5 mmol) in DCM (15 mL) was addedDess-Martin (1.28 g, 3.0 mmol) in one portion at 0° C. under N₂. Themixture was stirred at 27° C. for 2 h. The reaction was quenched withsat. aq. NaHCO₃ and sat. aq. Na₂S₂O₃ (v:v=1:1, 60 mL). The mixture wasextracted with EA (2×50 mL). The combined organic phase was washed withbrine (80 mL), dried over anhydrous Na₂SO₄ and filtered. The filtratewas concentrated in vacuum to afford 302-8 (1.21 g, crude) as a yellowsolid.

To a stirred solution of Methyl-triphenyl-phosphonium bromide (1.64 g,4.6 mmol) in anhydrous THF (5.5 mL) was added t-BuOK (1 M, 4.4 mL) at 0°C. dropwise. The mixture was stirred at 27° C. for 1 h. A solution of302-8 (1.21 g crude, 1.5 mmol) in THF (5 mL) was added at 0° C. Themixture was stirred at 27° C. for 12 h. The reaction was quenched withsat. aq. NH₄Cl (70 mL), extracted with EA (2×50 mL). The organic layerwas washed with brine (80 mL), dried over MgSO₄, filtered and evaporatedto dryness to give a light yellow solid, which was purified by columnchromatography (15 EA in PE) to give 302-9 (970 mg, 80%) as a whitesolid.

To a solution of 302-9 (970 mg, 1.2 mmol) in CH₃CN (10 mL) was addedTPSCl (877 mg, 3.0 mmol), DMAP (363 mg, 3.0 mmol) and TEA (301 mg, 3.0mmol) at 27° C. under N₂. The mixture was stirred at 27° C. for 1.5 h.NH₃.H₂O (5 mL) was added, and the reaction mixture was stirred at 27° C.for 2 h. The reaction was quenched with sat. aq. NH₄Cl (60 mL), and thenextracted with EA (2×40 mL). The combined organic phase was washed withbrine (60 mL), dried over anhydrous Na₂SO₄, filtered and concentrated invacuum. The residue was purified by silica gel chromatography (2% MeOHin DCM) to afford 302-10 (810 mg, 83%) as a white solid.

To a solution of 302-10 (500 mg, 0.6 mmol) in MeOH (15 mL) was addedNH₄F (455 mg, 12.3 mmol) at 27° C. under N₂. The mixture was stirred at70° C. for 12 h. The mixture was then cooled to R.T. and filtered. Thefiltrate was concentrated under reduced pressure. The residue waspurified by silica gel chromatography (5% MeOH in DCM) to afford crude302 (120 mg, crude). The crude was purified by prep-HPLC (neutralcondition) to give 302 (86 mg, 45%) as a white solid. MS: m/z=304[M+H]⁺.

Example 180 Compound 303

To a mixture of 303-1 (30 g, 122.85 mmol) and 1,1-dimethoxycyclopentane(86 g, 660.93 mmol) in DCE (200 mL) was added TsOH.H₂O (2.34 g, 12.29mmol) in one portion at RT. The mixture was heated to 70° C. and stirredfor 14 h. The mixture was cooled to R.T. and concentrated under reducedpressure. The residue was purified by column chromatography (1-10% MeOHin DCM) to give 303-2 (25 g, 65.6%) as a white solid.

To a solution of 303-2 (20 g, 64.45 mmol) in anhydrous CH₃CN (200 mL)was added IBX (19.85 g, 70.9 mmol) at RT. The mixture was refluxed for18 h. and then cooled to 0° C. The precipitate was filtered-off, and thefiltrate was concentrated to give crude 303-3 (20 g, 100%) as a yellowsolid.

To a solution of 303-3 (20 g, 64.87 mmol) in 1,4-dioxane (200 mL) wereadded 37% HCHO (20 mL) and 2.0 M NaOH aq. solution (40 mL) at 0° C. Themixture was stirred at R.T. overnight and then neutralized with AcOH topH=7. The solution was treated with NaBH₄ (4.91 g, 129.74 mmol) at 20°C. The mixture was stirred at R.T. for 1 h. The reaction was quenchedwith sat. aq. NH₄Cl. The mixture was extracted with EA (3×100 mL). Theorganic layer was dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified by silica gel column chromatography(1-3% MeOH in DCM) to give 303-4 (9 g, 40.8%) as a white solid.

To a solution of 303-4 (15.50 g, 45.54 mmol) in anhydrous pyridine(80.00 mL) was added DMTrCl (18.52 g, 54.65 mmol) in anhydrous DCM(20.00 mL) dropwise at −30° C. The mixture was stirred at 25° C.overnight. The solution was treated with MeOH and concentrated at lowpressure. The residue was purified by column chromatography (50% EA inPE) to give 303-5 (10.59 g, yield 32.56%) as a yellow solid.

To a solution of 303-5 (2.90 g, 4.51 mmol) in CH₂Cl₂ (20.00 mL) wasadded AgNO₃ (1.15 g, 6.77 mmol), imidazole (767.60 mg, 11.28 mmol) andTBDPSCl (1.86 g, 6.77 mmol). The mixture was stirred at 25° C. for 14 h.The precipitate was filtered off, and the filtrate was washed with waterand dried over anhydrous Na₂SO₄. The solvent was removed at lowpressure. The crude residue was purified by silica gel chromatography(PE:EA=5:1) to afford 303-6 (2.79 g, 63.19%) as a yellow solid.

303-6 (2.79 g, 3.17 mmol) was dissolved in 80% HOAc aq. solution (50mL). The mixture was stirred at 25° C. for 4 h. The solution was treatedwith MeOH and concentrated at low pressure. The residue was purified bysilica gel column chromatography (PE:EA=4:1) to give 303-7 (0.9 g, 44%)as a yellow solid.

To a solution of 303-7 (1.50 g, 2.59 mmol) in anhydrous DCM (20 mL) wasadded Dess-Martin periodinane (1.32 g, 3.11 mmol) at 0° C. under N₂. Themixture was stirred at R.T. for 4 h. The reaction was quenched by theaddition of Na₂S₂O₃/sodium bicarbonate saturated aqueous solution. Themixture was stirred for 15 mins. The organic layer was separated, washedwith diluted brine and concentrated under reduced pressure. The cruderesidue was purified by silica gel column chromatography (20% EtOAc inPE) to give 303-8 (1.12 g, yield 67.48%) as a white solid.

To a solution of PPh₃CH₃Br (1.49 g, 4.16 mmol) in anhydrous THF (15 mL)was added n-BuLi (0.41 mL, 3.47 mmol) at −70° C. under N₂. The mixturewas stirred at 0° C. for 0.5 hour. A solution of 303-8 (800.00 mg, 1.39mmol) in anhydrous THF (3 mL) was added dropwise at 0° C. under N₂. Themixture was stirred 25° C. for 2 h. The reaction was quenched with sat.NH₄Cl solution and extracted with EtOAc (3×60 mL). The organic phase waswashed with brine, dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The crude product was purified by silica gel columnchromatography (20% EtOAc in PE) to give 303-9 (504 mg, 56.78%) as awhite solid.

To a solution of 303-9 (500 mg, 869.96 mol) in anhydrous CH₃CN (10.00mL) was added 2,4,6-triisopropylbenzenesulfonyl chloride (526.95 mg,1.74 mmol), DMAP (212.57 mg, 1.74 mmol) and Et₃N (1.83 g, 18.04 mmol) atRT. The mixture was stirred at 25° C. for 1 h. NH₃.H₂O (5.00 mL) wasadded, and the mixture was stirred for 1 h. The mixture was extractedwith EA and washed with brine, 0.1 M HCl and sat. aq. NaHCO₃. Theorganic phase was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by silica gel chromatography (EtOAc)to give 303-10 (307 mg, 55.36%) as a yellow solid.

To a solution of 303-10 (307 mg, 535.08 μmol) in MeOH (4 mL) was addedNH₄F (814 mg, 20 mmol) at 25° C. under N₂. The mixture was stirred at65° C. for 16 h. The solution was filtered and evaporated to dryness.The residue was purified by silica gel column (EA:MeOH=50:1) to give303-11 (130 mg, 65.2%) as a white solid.

303-11 (108 mg, 322.05 μmol) was treated with HCl:MeOH (6 mL, 1N) at 25°C. under N₂. The mixture was stirred at 25° C. for 1 h. The aqueousphase was extracted with EA (3×10 mL). The residual aqueous solution waslyophilized to afford 303 (80.00 mg yield 87.65%) as a yellow solid.ESI-MS: m/z 270 [M+H]⁺.

Example 181 Compound 304

To a mixture of K₂CO₃ (2.40 g, 17.35 mmol) and TsN₃ (1.37 g, 6.94 mmol)in CH₃CN (20 mL) was added 1-dimethoxyphosphorylpropan-2-one (1.15 g,6.94 mmol) in one portion at 25° C. under N₂. The mixture was stirred at25° C. for 2 h. A solution of 304-1 (2.00 g, 3.47 mmol) in MeOH (20 mL)was added in one portion at 25° C. under N₂, and the mixture was stirredat 25° C. for 16 h. The mixture was poured into water and extracted withEtOAc (2×30 mL). The combined organic phase was washed with brine, driedover anhydrous Na₂SO₄, filtered and concentrated in vacuum. The residuewas purified by prep-HPLC (TFA buffer) to give 304-2 (1.50 g, 75%) as awhite solid.

To a solution of 304-2 (600 mg, 1.05 mmol) in dry CH₃CN (60 mL) wasadded TEA (212 mg, 2.10 mmol), DMAP (256 mg, 2.10 mmol) and2,4,6-triisopropylbenzenesulfonyl chloride (635 mg, 2.10 mmol) at 0° C.The mixture was stirred at 25° C. for 1 h. NH₃.H₂O (10 mL) was added at25° C. The mixture was stirred at 25° C. for 1 h. The reaction wasquenched with sat. NH₄Cl solution, and extracted with EtOAc (2×10 mL).The organic phase was washed with brine, dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The residue was purified by silica gelchromatography (PE:EA=3:1 to 0:1), and prep-TLC (DCM:MeOH=10:1) to give304-3 (380 mg, 63%) as a white solid.

A solution of 304-3 (300 mg, 0.52 mmol) and NH₄F (194 mg, 5.25 mmol) indry MeOH (5 mL) was stirred at 65° C. for 12 h. The mixture wasconcentrated at low pressure. The residue was purified by silica gelcolumn chromatography (DCM:MeOH=50:1 to 10:1) to afford 304-4 (140 mg,80%) as a white solid.

A solution of 304-4 (100 mg, 0.30 mmol) in 1 N HCl:MeOH (5 mL) wasstirred at 25° C. for 2 h. The mixture was concentrated under 40° C. Theresidue was washed with CH₃CN (5×2 mL) to give 304 (61 mg, 67%) as awhite solid. ESI-LCMS: m/z 268.1 [M+H]⁺.

Example 182 Compound 305

To a solution of N-(tert-Butoxycarbonyl)-L-valine (8.06 g, 37.1 mmol,1.5 eq.) in anhydrous ACN (60 mL) was added carbonyldiimidazole (6.01 g,37.1 mmol, 1.5 eq.). The reaction was stirred for 1 h at RT and thencooled to 0° C. A solution of 44 (14.9 g, 24.7 mmol, 1 eq.) in anhydrousACN (50 mL) was added to the cooled solution of N-BOC-valineimidazolide, and the resulting solution was treated with Et₃N (6.4 mL,49.4 mmol, 2 eq.). The reaction was allowed to proceed for 1 h at 0° C.The reaction was quenched 1M citric acid to pH 2-3 (150 mL), stirred for15 mins and diluted with IPAC (200 mL). The organic layer was separated,washed sequentially with water and half sat. sodium bicarbonate andwater (2×). The organic layer was concentrated under reduced pressure,and the residue was dissolved in MTBE (125 mL) under gentle heating (40°C.) to afford precipitation of the target compound. The solid was agedovernight at 0° C. and isolated by filtration to obtain 305-1 (18.0 g,90.9%) as a white solid. MS: m/z=802 [M+1]⁺.

A stirred slurry of 305-1 (2.4 g, 3 mmol) in IPAC (45 mL) was treatedwith methanesulfonic acid (0.39 mL, 6 mmol, 2 eq.), and the mixture wasstirred at 40° C. After 1 h, methanesulfonic acid (2×0.2 mL, 6 mmol, 2eq.) was added, and the temperature was increased to 50° C. After 5 h,the mixture was cooled to RT. The solid was filtered off, washed withIPAC and dried under vacuum to yield 305 (2.0 g, 83%).

Example 183 Triphosphates

Dry nucleoside (0.05 mmol) was dissolved in the mixture of PO(OMe)₃ (0.7mL) and pyridine (0.3 mL). The mixture was evaporated in vacuum for 15mins at bath temperature (42° C.), than cooled down to RT.N-Methylimidazole (0.009 mL, 0.11 mmol) was added followed by POCl₃ (9μL, 0.11 mmol), and the mixture was kept at RT for 20-40 mins. Thereaction was controlled by LCMS and monitored by the appearance ofcorresponding nucleoside 5′-monophosphate. After completion,tetrabutylammonium salt of pyrophosphate (150 mg) was added, followed byDMF (0.5 mL) to get a homogeneous solution. After 1.5 h at ambienttemperature, the reaction was diluted with water (10 mL) and loaded onthe column HiLoad 16/10 with Q Sepharose High Performance. Separationwas done in a linear gradient of NaCl from 0 to 1N in 50 mM TRIS-buffer(pH 7.5). Triphosphate was eluted at 75-80% B. Corresponding fractionswere concentrated. Desalting was achieved by RP HPLC on Synergy 4 micronHydro-RP column (Phenominex). A linear gradient of methanol from 0 to30% in 50 mM triethylammonium acetate buffer (pH 7.5) was used forelution. The corresponding fractions were combined, concentrated andlyophilized 3 times to remove excess of buffer. Examples of compoundmade according to this procedure are provided in Table 2.

TABLE 2 31P NMR Structure MS [M − 1] P(α) P(β) P(γ) 3

540.4 −10.90 −11.03(d) −23.38(t) −11.91 −12.03(d) 19

556.2 −10.92 −11.03(d) −23.18(t) −11.86 −11.98(d) 29

516.1  −7.49  −7.61(d) −22.42(t) −12.17 −12.30(d) 34

568.2  −5.60  −5.72(d) −21.13(bs) −10.93 −11.05(d) 37

539.3 −10.02 −10.36(d) −20.72(t) −11.27 −11.40(d) 58

510.8 −10.87 −10.99(d) −23.35(t) −11.76 −11.89(d) 59

543.8 −10.53 −10.66(d) −23.23(t) −11.63 −11.75(d) 61

538.9 −10.61 −10.73(d) −23.20(t) −11.74 −11.86(d) 62

538.9 −10.92 −11.04(d) −23.33(t) −11.81 −11.93(d) 72

529.3  −5.25  −5.37(d) −20.53(t) −11.42 −11.53(d) 73

551.4 −10.90 −11.02(d) −23.27(t) −11.87 −11.99(d) 74

535.0  −5.41  −5.53(d) −23.27(t) −11.39 −11.51(d) 79

529.2 −10.86 −10.98(d) −23.23(t) −11.85 −11.9(d) 80

535.0 −10.86 −10.98(d) −23.21(t) −11.81 −11.94(d) 81

529.2 −10.64 −10.73(d) −20.78(t) −11.42 −11.56(d) 82

534.3 −10.75 −10.89(d) −23.19(t) −11.46 −11.58(d) 91

528.0 −10.13(bs) −23.16(t) −11.64 −11.81(d) 92

528.9 −11.05 −11.08(d) −23.46(t) −11.79 −11.91(d) 93

561.7 −10.73 −10.85(d) −23.23(t) −11.63 −11.75(d) 94

534.0 −10.92 −10.64(d) −23.38(t) −11.61 −11.73(d) 95

512.8 −10.98 −11.11(d) −23.46(t) −11.70 −11.8(d) 101

556.2 −10.92 −10.07(d) −23.34(t) −11.70 −11.82(d) 103

566.0  −6.26  −6.39(d) −22.45(t) −11.66 −11.84(d) 107

539.3  −5.36(d) −20.72(t) −11.40(d) 111

564.0 −10.94 −11.06(d) −23.25(t) −11.85 −11.97(d) 114

546.9  −8.53(bs) −22.61(bs) −21.17 −12.29(d) 115

564.4 −11.05(bs) −23.25(bs) −11.96 −12.08(d) 123

566.0 −10.92 −11.04(d) −23.18(t) −11.93  −1(d) 124

513.8  −8.66(bs) −22.80(t) −12.17 −12.29(d) 132

579.4 −10.31 −10.44(d) −23.08(t) −11.81 −11.92(d) 133

563.0 −10.79 −10.91(d) −23.24(t) −11.80 −11.92(d) 147

517.1 −13.60 −13.72(d) −25.98(t) −15.05 −15.17(d) 149

533.3 −10.89 −11.01(d) −23.31(t) −12.49  −1(d) 162

570.4  −9.25  −9.28(d) −22.82(t) −11.29 −11.42(d) 163

542.2  −5.39  −5.40(d) −20.71(t) −11.52 −11.63(d) 164

529.8 −10.72(bs) −23.20(t) −11.73 −11.84(d) 166

548.2 −10.93 −11.05(d) −23.35(t) −12.00 −12.13(d) 167

535.3 −12.86 −12.98(d) −25.60(t) −14.24 −14.36(d) 168

534.3  −7.78(bs) −22.30(t) −11.70(bs) 184

523.1  42.93 −23.28  −7.94 185

523.3  42.69 −22.93  −6.22 202

529.8  −6.53(m) −22.27(m) −11.27 203

545.9  −8.6(br) −22.80(t) −11.35(d) 205

—  −4.97(m) −20.04(m) −10.72(m) 208

539.5  −7.42(bs) −22.57(t) −12.23 −12.34(d) 209

513.1  −6.36  −6.49(d) −22.49(t) −12.20 −12.33(d) 210

547.3 −10.95 −11.07(d) −23.32(t) −11.91 −12.03(d) 215

526.8 −10.96 −11.08(d) −23.33(t) −12.41 −12.53(d) 236

527   −10.68 −10.80(d) −23.35(t) −12.30 −12.42(d) 237

540.5 −10.91 −11.03(d) −23.38(t) −12.24 −12.37(d) 238

539   −10.88 −10.99(d) −23.41(t) −12.15 −12.27(d) 239

529   −10.83 −10.95(d) −23.27(t) −12.25 −12.37(d) 240

538.4  −9.19(bs) −22.50(t) −12.04(bs) 241

536.0 −10.69 −10.81(d) −23.27(t) −11.72 −12.85(d) 242

548.2 −10.85 −10.97(d) −23.27(t) −11.62 −11.74(d) 243

510.1 −10.55 −10.67(d) −23.27(t) −11.72 −12.85(d) 244

544.9 −10.97 −11.05(d) −23.28(t) −11.77 −12.89(d) 245

577.6 −10.42 −10.54(d) −23.06(t) −11.61 −12.73(d) 246

554.0 −10.85 −10.96(d) −23.24(t) −11.52 −11.64(d) 249

552.4  −6.17(bs) −21.02(t) −10.09(bs) 251

541.4 −10.87 −11.99(d) −23.21(t) −11.72 −11.84(d) 252

553.4 −10.91 −11.03(d) −23.31(t) −11.74 −11.87(d) 253

555.6  −8.63  −8.76(d) −24.61(t) −13.90 −14.03(d) 254

551.4  −9.74  −9.86(d) −22.89(t) −11.46 −11.58(d) 255

553.4 −10.98 −11.10(d) −23.38(t) −11.86 −11.98(d) 256

547.2 −10.91 −11.03(d) −23.33(t) −11.79 −11.91(d) 257

533.4 −10.78(br.s) −23.22(t) −12.24 −12.36(d) 258

546.3 −10.52(bs) −23.05(t) −11.64 −11.76(d) 261

496.9  −8.24  −8.36(d) −21.66(t) −11.14 −11.26(d) 262

520.4 −10.87 −10.97(d) −23.34(t) −11.86 −11.97(d) 263

513.8  −8.20(bs) −22.74(t) −11.52 −11.64(d) 264

514.9  −9.95 −10.08(d) −23.14(t) −11.64 −11.76(d) 282

547.0 −10.78 −10.91(d) −23.31(t) −11.84 −11.96(d) 292

557.4 −10.96 −11.09(d) −23.35(t) −11.93 −12.05(d) 296

537.4 −10.90 −11.03(d) −23.35(t) −11.84 −11.96(d) 297

514.0 −10.27 −11.39(d) −23.18(t) −11.39 −11.51(d) 299

516.2  −9.52(br.s) −22.74(br.s) −11.75(br.s) 300

538.0 −10.15(br.s) −22.86(t) −11.28 −11.40(d) 301

526.2  −9.97(br.s) −22.81(t) −12.12 −12.23(d) 322

524.6 −11.68(d) −23.15(t) −11.72(d) 323

498.2 −11.72(d) −23.30(t) −10.90(d) 324

521.3  −9.23(d) −22.57(t)  −8.06(d) 325

552.3 −12.17(d) −22.96(t) −10.23(d) 326

553.0 −11.79(d) −22.65(t) −10.40(br.s) 327

553.0 −11.60(d) −22.98(t) −10.70(br.s) 328

557.3 −11.78(d) −22.33(t)  −8.76(br.s) 329

517.2 −11.04(d) −23.42(t) −12.31(d) 330

516.6  −9.80(br.s) −23.12(t) −12.09(br.s)

Example 184 Compound 307

To a solution of 307-1 (1.2 g, 2.09 mmol) in DCE (40 mL) was added TFA(2 mL). The mixture was stirred at RT for 1 h. The mixture wasconcentrated under reduced pressure, and the residue was purified bycolumn chromatography (3% MeOH in DCM) to give 307-2 (600 mg, 95.3%) asa white solid.

To a solution of 307-2 (600 mg, 1.99 mmol) in pyridine (4 mL) was addedimidazole (677 mg, 9.95 mmol) and TBSCl (900 mg, 5.97 mmol) at RT. Themixture was stirred at 60° C. for 16 h, and then concentrated underreduced pressure. The residue was diluted with EA (40 mL) and washedwith brine (20 mL). The organic layer was dried over anhydrous MgSO₄ andfiltered. The filtrate was concentrated under reduced pressure, and theresidue was purified by column chromatography (10% EA in PE) to give307-3 (700 mg, 65.7%) as a white solid.

To a solution of 307-3 (700 mg, 1.32 mmol) in DCM (52 mL) was added NIS(356 mg, 1.58 mmol) and TFA (1.3 mL). The mixture was stirred at 60° C.for 3 h. After cooling to RT, the solution was extracted with DCM (30mL), washed with sat. aq. NaHCO₃ and brine (20 mL), dried over anhydrousNa₂SO₄ and filtered. The filtrate was concentrated under reducedpressure. The residue was purified by column chromatography (10% EA inPE) to give 307-4 (400 mg, 46.2%) as a white solid.

A mixture of 307-4 (327 mg, 498 μmol), Bu₃SnH (174 mg, 598 μmol) and2,2′-azobis(2,4-dimethylvaleronitrile) (25 mg, 100 mol) in THF-d₈ (10mL) was stirred at 90-100° C. for 3 h. The mixture was concentratedunder reduced pressure. and the residue was purified by columnchromatography (10% EA in PE) to give 307-5 (180 mg, 68.00%) as a whitesolid.

To a solution of 307-5 (210 mg, 395 mol) in anhydrous MeCN (2 mL) wereadded DMAP (121 mg, 989 mol), Et₃N (100 mg, 989 mol) and2,4,6-triisopropylbenzene-1-sulfonyl chloride (299 mg, 989 mol) at RT.The mixture was stirred at RT for 16 h. NH₃.H₂O (1 mL) was added, andthe mixture was stirred for 1 h. The mixture was diluted with EA (15 mL)and washed with sat. aq. NH₄Cl (15 mL). The organic layer was dried overanhydrous Na₂SO₄ and filtered. The filtrate was concentrated underreduced pressure, and the residue was purified by column chromatography(2% MeOH in DCM) to give the crude product. The crude product waspurified by prep-TLC (10% MeOH in DCM) to give 307-6 (200 mg, 95.42%) asa white solid.

To a solution of 307-6 (200 mg, 0.38 mmol) in MeOH (2 mL) was added NH₄F(210 mg, 5.66 mmol) at RT. The mixture was stirred at 90-100° C. for 16h. The mixture was filtered, and the filtrate was concentrated underreduced pressure. The residue was purified by column chromatography (10%MeOH in DCM) to give the crude product. The crude product was purifiedby prep-HPLC (neutral condition) to give 307 (70 mg, 61.8% yield, 78.4%deuterium) as a white solid. ESI-TOF-MS: m/z=302.1 [M+H]⁺, 603.2[2M+H]⁺.

Example 185 Compound 321

The diphosphate, 321, can be prepared using a similar procedure topreparing the triphosphate of Example 183 with the replacement oftetrabutylammonium salt of pyrophosphate with tetrabutylammoniumphosphate (75 mg) and using 0.3 mL of DMF to get the homogeneoussolution.

Example 186 Compound 308

To a solution of 308-1 (22.80 g, 99.91 mmol) in anhydrous pyridine (200mL) was added DMTCl (37.24 g, 109.90 mmol), and the mixture stirred at25° C. for 12 h. The reaction was quenched with a sat. NH₄Cl solution(200 mL), and extracted with EA (3×200 mL). The combined organic layerswere washed with brine (2×100 mL), dried over anhydrous Na₂SO₄ andconcentrated under reduced pressure. The residue was purified by columnchromatography (PE:EA=2:1 to 0:1) to give the desired product (43.00 g,72.94 mmol) as a yellow foam.

To a solution of this product (20.00 g, 37.70 mmol), AgNO₃ (6.40 g,37.70 mmol) and imidazole (5.13 g, 75.39 mmol) in DMF (200.00 mL) wasadded, followed by TBSCl (8.52 g, 56.54 mmol) at 0° C. The mixture wasstirred at 25° C. for 12 h, and then the mixture was concentrated underreduced pressure to remove the DMF. The residue was diluted withice-water (300 mL) and extracted with EA (3×100 mL). The combinedorganic layers were washed with brine (3×50 mL), dried over anhydrousNa₂SO₄, filtered and concentrated under reduced pressure. The residuewas purified by column chromatography (PE:EA=3:1 to 1:1) to give1-[(2R,4S,5R)-5-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-4-[tert-butyl(dimethyl)silyl]oxy-tetrahydrofuran-2-yl]pyrimidine-2,4-dione(15.70 g, 24.35 mmol) as a white solid.

A solution of1-[(2R,4S,5R)-5-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-4-[tert-butyl(dimethyl)silyl]oxy-tetrahydrofuran-2-yl]pyrimidine-2,4-dione(20.00 g, 31.02 mmol) in AcOH (105 g, 1.40 mol) was stirred at 25° C.for 1 h. The reaction was quenched with MeOH (100 mL), and the mixturewas concentrated under reduced pressure. The residue was diluted withwater (100 mL). The solution was neutralized with solid NaHCO₃ to pH=7,and extracted with EA (3×100 mL). The combined organic layers werewashed with brine (100 mL), dried over anhydrous Na₂SO₄ and concentratedat low pressure. The residue was purified by column chromatography(PE:EA=5:1 to 0:1) to give 308-2 (8.90 g, 20.79 mmol) as a white solid.

To a stirred solution of 308-2 (3.42 g, 9.99 mmol) in dioxane (15.00 mL)and DMSO (3.00 mL) was added DCC (6.18 g, 29.97 mmol) and Py.TFA (1.93g, 9.99 mmol) at 0° C. The mixture was stirred at 25° C. for 2 h. Thesolution was diluted with EA (50 mL), and the solid was removed byfiltration. The filtrate was washed with brine (30 mL). The organiclayer was dried over anhydrous Na₂SO₄, and concentrated at low pressure.The residue was used in the next step without further purification.

To a solution of the residue from the previous step (3.4 g) andformaldehyde (aq., 3 mL) in dioxane (20 mL) was added 2.0 M NaOH (aq., 5mL) in one portion at 25° C. The mixture was stirred at 25° C. for 16 h.The mixture was cooled to 0° C. and neutralized with AcOH to pH=7. Thesolution was treated with NaBH₄ (452 mg, 11.952 mmol) at 0° C. Themixture was stirred at 25° C. for 30 mins, and the reaction was thenquenched with sat. aq. NH₄Cl (100 mL). The mixture was extracted with EA(2×100 mL). The organic phase was dried over anhydrous Na₂SO₄, filteredand concentrated in vacuum. The residue was purified by columnchromatography (DCM:MeOH=20:1 to 10:1) to afford 308-3 (1.43 g, 38.4%)as a white solid.

To a solution of 308-3 (1.43 g, 3.84 mmol) in DCM (10.00 mL) was addedTf₂O (2.38 g, 8.45 mmol) and pyridine (1.51 g, 19.2 mmol) at 0° C., andthe mixture stirred at 25° C. for 1 h. The reaction was quenched byice-water (20 mL) at 0° C., and then extracted with DCM (2×30 mL). Thecombined organic layers were dried over anhydrous Na₂SO₄, filtered andconcentrated under reduced pressure. The residue was purified by columnchromatography (DCM:MeOH=40:1) to give 308-4 (1.60 g, 2.14 mmol) as ayellow foam.

To a solution of 308-4 (1.60 g, 2.51 mmol) in DCM (10.00 mL) was addedTEA (1.27 g, 12.57 mmol), and the mixture was stirred at 25° C. for 16h. The reaction was quenched with 1.0 M HCl solution to pH=7, and thenextracted with DCM (30 mL). The organic layer was washed with brine (20mL), dried over anhydrous Na₂SO₄, and concentrated at low pressure. Theresidue was purified by column chromatography (DCM:MeOH=40:1 to 30:1) togive 308-5 (1.10 g, 81.07%) as a yellow solid.

To a solution 308-5 (1.10 g, 2.27 mmol) in DMF (10.00 mL) was added NaN₃(441.84 mg, 6.80 mmol), and the mixture was stirred at 25° C. for 12 h.The reaction was quenched with H₂O (3 mL), and extracted with EA (3×50mL). The combined organic layers were washed with brine (50 mL), driedover anhydrous Na₂SO₄ and concentrated at low pressure to give 308-6(800.00 mg, 92.87%) as a yellow solid.

To a solution of 308-6 (800.00 mg, 2.11 mmol) in THF (20.00 mL) wasadded NaOH solution (1.05 mL, 2.11 mmol, 2.0 M), and the mixture wasstirred at 25° C. for 12 h. The mixture was diluted with EA (20 mL), andwashed with brine (15 mL). The solution was dried over anhydrous Na₂SO₄and concentrated under reduced pressure to give 308-7 (821.00 mg,97.89%) as a yellow solid.

To a solution of 308-7 (596 mg, 1.50 mmol) in DCM (10 mL) was addedTBSCl (452.16 mg, 3.00 mmol) and imidazole (306.36 mg, 4.50 mmol), andthe mixture stirred at 25° C. for 5 h. The mixture was diluted with DCM(20 mL). The solution was washed with brine, dried over anhydrous Na₂SO₄and concentrated under reduced pressure. The residue was purified bycolumn chromatography (DCM:MeOH=40:1 to 30:1) to give 308-8 (750 mg,87.93%) as a white solid.

To a solution of 308-8 (600 mg, 1.17 mmol) and TEA (296 mg, 2.93 mmol)in CH₃CN (10 mL) was added TPSCl (862 mg, 2.93 mmol). The mixture washeated to 40° C. for 5 h. The reaction was quenched with 0.5 M HClsolution to pH=6. The solution was extracted with EA (3×20 mL). Theorganic layer was dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was treated with NH₃/THF (20 mL, 10 M). Thesolution was stirred at 25° C. for 16 h, and then concentrated underreduced pressure. The residue was purified by column chromatography(DCM:MeOH=30:1 to 20:1) to give the crude product (500 mg). The crudeproduct was purified by prep-TLC (DCM:MeOH=10:1) to give 308-9 (310 mg,52%) as a white solid.

To a solution of 308-9 (310 mg, 606.9 mol) in THF (5 mL) was added TBAFin THF (2 mL, 1.0 M) at 25° C. The solution was stirred at 25° C. for0.5 h. The mixture was concentrated at low pressure. The residue waspurified by prep-HPLC (HCl system) to give 308 (86 mg, 50.2%) as a whitesolid. ESI-TOF-MS: m/z=283.1 [M+H]⁺, 565.3 [2M+H]⁺.

Example 187 Compounds 309 and 310

To a solution of 309-1 (394 g, 2.62 mol) and imidazole (268 g, 3.93 mol)in DMF (3 L), was added TBDPSCl (756.14 g, 2.75 mol) in one portion at25° C. The mixture was heated to 50° C. and stirred for 12 h. Themixture was poured into water/brine (v:v=1:1) (6 L) and stirred for 20mins. The mixture was extracted with EA (2×4 L). The combined organicphase was washed with sat. brine (2×4 L), dried over anhydrous Na₂SO₄and concentrated in vacuum to give 309-2 (800 g, crude) as a yellowsolid.

To a solution of 309-2 (1000 g, 2.57 mol) and 2,2-dimethoxypropane (450g, 4.32 mol) in DCM (6 L), was added TsOH.H₂O (490 g, 2.57 mol) in oneportion at 25° C. The mixture was stirred for 0.5 h. The reaction wasquenched by water (1 L). The organic layer was washed with water (2×4L), dried over anhydrous Na₂SO₄ and concentrated in vacuum to give 309-3(1.1 kg, crude), which was used directly for next step.

A mixture of 309-3 (1.0 kg, 2.33 mol) and NH₄F (198 g, 5.36 mol) in MeOH(3 L) was stirred to reflux for 4 h. After the solvent was evaporated,the crude product was purified by silica gel (PE:EA=1:1) directly togive crude 309-4, which was recrystallized (PE:EA=1:1) to give pure309-4 (170 g, 38.4% yield) as a white solid. ¹H-NMR (400 MHz, CD3OD),δ=5.90 (d, J=4 Hz, 1H), 4.52 (d, J=4 Hz, 1H), 4.15 (s, 1H), 4.0-3.97 (m,1H), 3.75-3.65 (m, 2H), 1.50 (s, 3H), 1.31 (s, 3H).

To a solution of 309-4 (300 g, 1.58 mol) in DMF (4 L) was added NaH(83.3 g, 3.47 mol) by portions at 0° C., and the mixture was stirred at25° C. for 1 h. BnBr (553 g, 3.23 mol) was added, and the mixture wasstirred at 25° C. for 1 h. The reaction was quenched by NH₄Cl (sat., 1L) and water (2 L). The solution was extracted with EA:PE (2×3 L,v:v=1:1). The combined organic layer was concentrated in vacuum. Theresidue was purified by silica gel chromatography (PE:EA=50:1) to afford309-5 (505 g, 79.4%) as a yellow oil.

To a solution of 309-5 (330 g, 891 mmol) in MeOH (1500 mL) was addedH₂SO₄ (conc. 20 mL, 406 mmol) dropwise at 25° C. The mixture was heatedto 60° C. for 2 h. After the mixture was cooled to 25° C., the mixturewas adjusted to pH to 7-8 with HCl (2 N, ˜160 mL). The solution wasdiluted with EA (1.5 L). The organic layer was washed with H₂O (2×1 L),dried over anhydrous Na₂SO₄ and concentrated in vacuum. The residue waspurified by silica gel chromatography (PE:EA=5:1) to afford pure 309-6(280 g, 78.3%) as a yellow oil.

To a solution of 309-6 (150 g, 435.54 mmol) and DMAP (69.2 g, 566 mmol)in DCM (1.5 L) was added Tf₂O (135.2 g, 479 mmol) slowly at −10° C.under N₂. The mixture was warmed to 25° C. and stirred for 1.5 h. Thereaction was quenched with water (600 mL), and adjusted pH to 4-5 withHCl (1 N). The organic layer was separated, and washed with NaHCO₃(sat., 1 L), brine (1 L), and dried over anhydrous Na₂SO₄. The solutionwas concentrated in vacuum to give 309-7 (207 g, crude) as a yellow oil.

A mixture of 309-7 (207 g, 435.50 mmol) and TBAF (1 M in THF, 870 mL)was stirred at 60-70° C. for 12 h. The solvent was evaporated at lowpressure. The residue was dissolved in EA (800 mL). The solution waswashed with water (3×500 mL), brine (500 mL) and dried over anhydrousNa₂SO₄. The solution was concentrated at low pressure. The residue waspurified by silica gel chromatography (PE:EA=20:1) to afford 309-8 (40g, 25.46%) as a light yellow oil. ¹H-NMR (400 MHz, CD₃OD) δ=7.36-7.33(m, 10H), 5.05 (d, J=8 Hz, 1H), 4.87 (m, 0.5H), 4.80-4.70 (m, 1.5H),4.62-4.53 (m, 3H), 4.36-4.30 (m, 1H), 4.18-4.05 (m, 2H), 3.70-3.53 (m,2H), 3.36 (s, 3H). ¹⁹F NMR (376 MHz, CDCl₃) δ=−209.48.

To a solution of 309-8 (50 g, 144.35 mmol) in MeOH (50 mL) was addedPd(OH)₂/C (13 g, 50% H₂O) under Ar. The suspension was degassed undervacuum and purged with H₂ several times. The mixture was stirred underH₂ (40 psi) at 40° C. for 8 h. After the catalyst was filtered off, thefiltrate was concentrated in vacuum to give 309-9 (23 g, 91%) as a graysolid.

To a solution of 309-9 (55 g, 331 mmol) and imidazole (31.55 g, 463.4mmol) in DCM (1 L) was added TBDPSCl (100 g, 364.13 mmol) slowly at 0°C. The mixture was stirred at 25° C. for 12 h. The reaction was quenchedwith water (100 mL), and then the mixture was concentrated. The residuewas dissolved in EA (500 mL). The solution was washed with water (2×500mL), dried over anhydrous Na₂SO₄ and concentrated at low pressure. Theresidue was purified by silica gel chromatography (PE:EA=5:1) to afford309-10 (74 g, 55%) as a colorless oil.

To a solution of 309-10 (70 g, 173 mmol) in DMF (750 mL) was added NaH(7.61 g, 190 mmol) at 0° C., and the mixture stirred at 25° C. for 1 hr.BnBr (32.55 g, 190.33 mmol) was added slowly at 0° C. under N₂. Themixture was stirred at 25° C. for 2 h, and the reaction was quenchedwith water (1000 mL). The solution was extracted by EA:PE (v:v=2:1,2×800 mL). The organic layer was separated and washed with brine:water(v:v=1:1, 2×500 mL). The organic layer was dried over anhydrous Na₂SO₄and concentrated at low pressure to give 309-11 (80 g, crude) as ayellow oil.

A mixture of 309-11 (100 g, 202.1 mmol) and NH₄F (15 g, 404.3 mmol) inMeOH (2000 mL) was stirred at 65° C. for 12 h. The mixture was cooled to25° C. and concentrated under reduced pressure. The residue was dilutedwith EA (500 mL) and washed with water (2×500 mL). The organic phase waswashed with sat. brine (500 mL), dried with anhydrous Na₂SO₄, filteredand concentrated in vacuum. The residue was purified by silica gelchromatography (PE:EA=8:1) to afford 309-12 (36 g, 69.5%) as a yellowoil.

To a solution of 309-12 (36 g, 148.4 mmol) and TEA (22.51 g, 222.4 mmol)in DCM (300 mL) was added BzCl (23 g, 163.1 mmol) dropwise at 25° C.under N₂, and the mixture was stirred at 25° C. for 12 h. The reactionwas quenched with water (500 mL). The organic layer was separated,washed by water (400 mL) and dried over anhydrous Na₂SO₄. The organiclayer was concentrated under reduced pressure to give 309-13 (55 g,crude) as a yellow oil.

A mixture of 309-13 (55 g, 152.62 mmol) in TFA:H₂O (500 mL, v:v=9:1) wasstirred at 25° C. for 30 h. The solution was evaporated in vacuum. Theresidue was diluted with EA (200 mL), and washed with NaHCO₃ (aq., 200mL). The organic layer was dried over anhydrous Na₂SO₄, and concentratedat low pressure. The residue was purified by silica gel (PE:EA=10:1) toafford 309-14 (45 g, 80.8% yield) as a yellow oil.

To a solution of 309-14 (45 g, 129.9 mmol) in EtOH (500 mL) was addedNaBH₄ (5.41 g, 142.9 mmol) at 25° C., and the mixture was stirred at 25°C. for 0.5 h. The reaction was quenched with aq. NH₄Cl (500 mL), andextracted with EA (2×300 mL). The organic layer was washed with brine(300 mL), and concentrated under reduced pressure. The residue waspurified by column chromatography (PE:EA=2:1) to give 309-15 (42 g, 94%yield) as a white solid. ¹H-NMR (400 MHz, MeOD), δ=8.05 (d, J=7.2 Hz,2H), 7.65-7.20 (m, 9H), 4.95 (m, 0.5H), 4.80-4.65 (m, 2H), 4.53-4.47 (m,2H), 4.15-4.07 (m, 1H), 4.00-3.85 (m, 3H). ¹⁹F NMR (376 MHz, MeOD)δ=−196.75.

A mixture of 309-15 (90 g, 258.4 mmol) in pyridine (500 mL) was treatedwith DMTrCl (92 g, 271 mmol) at 25° C. for 16 h. The solvent wasevaporated in vacuum. The residue was dissolved in EA (500 mL). Thesolution was washed with water (2×300 mL), dried over anhydrous Na₂SO₄and concentrated at low pressure to give 309-16 (145 g, crude) as ayellow solid.

To a solution of 309-16 (145 g, 223 mmol) in MeOH:THF (2000 mL, v:v=3:1)was added NaOMe (12 g, 53.8 mmol) in one portion. The mixture wasstirred at 25° C. for 1 h, and the reaction was quenched with CO₂(solid). The mixture was concentrated at low pressure. The residue wasdissolved in EA (200 mL). The solution was washed with water (300 mL)and brine (300 mL), dried over anhydrous Na₂SO₄ and concentrated at lowpressure. The residue was purified by silica gel chromatography(PE:EA=5:1) to give 309-17 (85 g, 70%) as a yellow oil.

To a solution of 309-17 (35.0 g, 64 mmol) in pyridine (200 mL) was addedTrtCl (21.42 g, 76.84 mmol) in one portion at 20° C. The mixture wasstirred at 20° C. for 15 h. The solution was evaporated in vacuum. Theresidue was dissolved in EA (300 mL). The solution was washed with water(2×200 mL). The organic layer was dried over anhydrous Na₂SO₄ andconcentrated at low pressure. The residue was purified by silica gelchromatography (PE:EA=20:1) to give 309-18 (31 g, 89.5%) as a yellowoil.

To a solution of 309-18 (31 g, 41.8 mmol) in CH₃CN (500 mL) was addedIBX (11.7 g, 41.8 mmol) in one portion at 20° C., and the mixture wasstirred at 80° C. for 2 h. The mixture was cooled, and then filtered.The filtrate was concentrated at low pressure to give 309-19 (32 g,crude) as a yellow oil.

To a solution of 309-19 (32 g, 40.6 mmol) and CsF (18.53 g, 122 mmol) inTHF (300 mL) was added TMSCF₃ (17.35 g, 122 mmol) at 15° C., and themixture was stirred at 15° C. for 18 h. The reaction was quenched withMeOH (5 mL). The solution was extracted with EA (300 mL), and washedwith water (2×200 mL). The organic layer was dried over anhydrous Na₂SO₄and concentrated at low pressure. The residue was purified by columnchromatography (PE:EA=8:1) to give 309-20 (25 g, 71.7%) as a yellow oil.¹⁹F NMR (376 MHz, CDCl₃) δ=−74.93, −74.95, −186.74, −186.83.

To a solution of 309-20 (50 g, 58.35 mmol) in THF (50 mL) was added AcOH(200 mL, 80%), and the mixture was stirred at 15° C. for 16 h. Themixture was then heated to 45° C. and stirred for 2 h. The solvent wasevaporated in vacuum (MeOH was added (5×5 mL) during evaporation). Theresidue was purified by column chromatography (PE:EA=20:1) to give309-21 (down spot, desired isomer) (7.4 g, 22.9%) as a yellow solid andthe by-product (17.1 g, 52.84%) (up spot) as a yellow solid. Down spot:¹H-NMR (400 MHz, CDCl₃), δ=7.50-7.25 (m, 20H), 4.85-4.65 (t, 2H),4.48-4.40 (m, 1H), 4.35 (m, 0.5 H), 4.25 (m, 0.5H), 3.75-3.65 (m, 3H),3.20 (d, J=12 Hz, 1H). ¹⁹F-NMR (376 MHz, MeOD), δ=−75.55, −190.067. Upspot: ¹H-NMR (400 MHz, CDCl₃), δ=7.50-7.25 (m, 20H), 4.98-4.80 (m, 1H),4.67 (d, J=12 Hz, 1H), 4.42-4.39 (m, 1H), 4.33-4.29 (m, 1H), 3.85-3.71(m, 2H), 3.65-3.60 (m, 1H), 3.54-5.52, (m, 2H). ¹⁹F-NMR (376 MHz, MeOD),δ=−75.455 (s, 3F), −189.53 (s, 1F).

To a solution of 309-21 (8.50 g, 15.3 mmol) in THF:DMSO (60 mL) wasadded IBX (4.29 g, 15.3 mmol), and the mixture was stirred at 35° C. for2 h. The solution was slowly warmed to 40° C., and the mixture wasstirred for 2 h. The mixture was filtered, and the filtrate wasconcentrated under reduced pressure. The residue was diluted with EA(100 mL) and washed with water (100 mL). The organic phase was driedover anhydrous Na₂SO₄, and concentrated under reduced pressure. Theresidue was purified by column chromatography (PE:EA=25:1) to give309-22 (8.0 g, 75%) as a yellow oil.

To a solution of 309-22 (4.50 g, 8.14 mmol) in pyridine (50 mL) wasadded Ac₂O (2.49 g, 24.4 mmol). The mixture was stirred at 15° C. for 3h. The reaction was quenched with MeOH (1 mL), and the solvent wasevaporated via vacuum. The residue was dissolved in EA (40 mL). Thesolution was washed with water (50 mL), dried over anhydrous Na₂SO₄, andconcentrated at low pressure. The residue was purified by columnchromatography (PE:EA=20:1) to give 309-23 (4.30 g, 88.8%) as acolorless oil. ¹H-NMR (400 MHz, CDCl₃), δ=7.50-7.20 (m, 20H), 6.45 (d,J=12 Hz, 1H), 4.90 (m, 0.5H), 4.77 (m, 0.5H), 4.70-4.55 (m, 3H), 3.40(dd, J=40 Hz, 2H), 1.79 (s, 3H). ¹⁹F-NMR (376 MHz, MeOD), δ=−73.92 (d,J=18 Hz, 3F), −204.95 (t, 1F).

To a solution of 309-23 (900 mg, 1.51 mmol) in MeOH (20 mL) was addedPd(OH)₂/C (50%, 0.6 g) under N₂ atmosphere. The suspension was degassedand purged with H₂ (3×). The mixture was stirred under H₂ (40 psi) at40° C. for 24 h, and then filtered. The filtrate was concentrated invacuum. The residue was purified by column chromatography (PE:EA=10:1)to give 309-24 (300 mg, 39.4%) as a yellow oil.

To a solution of 309-24 (200 mg, 396.5 mol) in DCM (2 mL) was added TFA(153 mg, 1.34 mmol) and Et₃SiH (365 mg, 3.14 mmol). The mixture wasstirred at 15° C. for 20 mins. The solvent was evaporated directly invacuum. The residue was purified by column chromatography (PE:EA=1:1) togive 309-25 (100 mg, 96%) as a white solid.

To a solution of 309-25 (100 mg, 381 mol) in DCM (2 mL) was added DMAP(46.60 mg, 381 mol) and TEA (115.8 mg, 1.14 mmol). BzCl (117.96 mg,839.19 mol) was added, and the mixture was stirred at 15° C. for 0.5 h.The reaction was quenched with HCl (0.3 N, 10 mL). The mixture wasextracted with CH₂Cl₂ (3×10 mL), and washed with water (10 mL). Theorganic phase was dried over anhydrous Na₂SO₄, and concentrated at lowpressure. The residue was purified by column chromatography (PE:EA=20:1)to give 309-26 (144 mg, 81%) as a yellow oil. ¹H-NMR (400 MHz, CDCl₃),δ=8.12 (d, J=7.6 Hz, 1H), 8.04 (d, J=7.6 Hz, 1H), 7.70-7.39 (m, 6H),6.57 (d, J=11 Hz, 1H), 6.02 (dd, J=22.8 Hz, J₂=4.8 Hz, 1H), 5.28 (dd,J₁=52 Hz, J₂=4.4 Hz, 1H), 4.74 (t, 2H), 1.96 (s, 3H). ¹⁹F-NMR, (376 MHz,MeOD), δ=−74.18 (d, J=18.8 Hz, 3F), −204.08 (t, 1F).

A mixture of uracil (457.54 mg, 4.08 mmol) and HMDS (3.85 g, 23.86 mmol)was stirred at 120° C. for 1 h, and the solvent was evaporated at lowpressure. 309-26 (480 mg, 1.02 mmol) was dissolved in CH₃CN (2 mL), andtreated with the above mixture. The mixture was taken up into amicrowave tube, and was treated with TMSOTf (1.60 g, 7.19 mmol). Themixture was heated at 140° C. for 4 h under microwave irradiation. Thereaction was quenched with MeOH, and the mixture was concentrateddirectly at low pressure. The residue was purified by columnchromatography (PE:EA=5:1) to give the crude product (2.5 g), which waspurified by prep-HPLC (TFA) to give two isomers (0.92 g). After theresidue was purified by SFC (AD-H_6_30-65 6MIN, OJ (250 mm*50 mm, 10um), Base-MeOH), 309-27a (α-isomer, 470 mg, 22%) and 309-27b (β-isomer,320 mg, 15%) were obtained as a white solid. 309-27a (α-isomer): ¹H-NMR(400 MHz, CDCl₃), δ=8.63 (s, 1H), 8.20-8.00 (m, 4H), 7.75-6.95 (m, 6H),6.63 (d, J=20.8 Hz, 1H), 6.10 (dd, J=23.6 Hz, J₂=4 Hz, 1H), 5.86 (d,J=6.8 Hz, 1H), 5.47 (d, J=54 Hz, 1H), 4.80 (s, 2H). ¹⁹F-NMR (376 MHz,MeOD), δ=−73.65 (d, J=16.4 Hz, 3F), −212.54 (t, 1F). 309-27b (β-isomer):¹H-NMR (400 MHz, CDCl₃), δ=8.48 (s, 1H), 8.15-8.00 (m, 4H), 7.60-7.25(m, 6H), 6.22 (dd, J=16 Hz, J₂=6.4 Hz, 1H), 5.95-5.20 (m, 3H), 4.80 (s,2H). ¹⁹F-NMR (376 MHz, MeOD), δ=−73.31 (d, J=11 Hz, 3F), −192.56 (t,1F).

A mixture of 309-27b (180 mg, 344 mol, 1.0 eq.) in NH₃/MeOH (7 M, 5 mL)was stirred at 15° C. for 16 h. The solvent was concentrated directly invacuum. The residue was purified by prep-HPLC (neutral condition,NH₄HCO₃) to give 310 (86 mg, 79.4%) as a white solid. ESI-MS: m/z 315.1[M+H]⁺.

To a solution of 309-27b (200 mg, 383 mol) in CH₃CN (2 mL) was addedDMAP (116 mg, 957 mol), TEA (97 mg, 957 mol), and2,4,6-triisopropylbenzenesulfonyl chloride (290 mg, 957 mol), and themixture stirred at 15° C. for 20 mins. The mixture was treated withNH₃.H₂O (2 mL), and the mixture was stirred at 15° C. for 10 mins. Themixture was extracted with EA (2×10 mL). The organic phase was driedover anhydrous Na₂SO₄ and concentrated at low pressure. The residue waspurified by column chromatography (PE:EA=2:1) and re-purified byprep-TLC (DCM:MeOH=15:1) to give 309-28 (90 mg, 45%) as a white solid.

A mixture of 309-28 (90 mg, 172.61 mol) in NH₃/MeOH (7 M, 3 mL) wasstirred at 15° C. for 16 h. The solvent was concentrated directly invacuum. The residue was purified by prep-HPLC (HCl condition) to give309 (30 mg, 55%) as a white solid. ESI-MS: m/z 314.0 [M+H]⁺.

Example 188 Compound 311

311-1 (2.3 g, 3.0 mmol) was treated with NH₃ in MeOH (50 mL, 10 M) at25° C. The mixture was stirred at 25° C. for 24 h. The mixture wasconcentrated under reduced pressure. The residue was purified by columnchromatography (10%-30% EtOAc in PE) to afford 311-2 (1.5 g, 70.8%) as awhite solid.

To a stirred solution of 311-2 (1.5 g, 2.26 mmol) in anhydrous DCM(15.00 mL) was added Dess-Martin (1.6 g, 3.84 mmol) in one portion at 0°C. under N₂. The mixture was stirred at 25° C. for 1.5 h. The reactionwas quenched with sat. Na₂S₂O₃ and sat. NaHCO₃ (v:v=1:1, 20 mL) at 0° C.The aqueous phase was extracted with DCM (3×30 mL). The combined organicphase was washed with sat. brine, dried over anhydrous Na₂SO₄, filteredand concentrated in vacuum to give 311-3 (1.6 g, crude), which was usedin the next step without further purification.

To a solution of methyl (triphenyl)phosphonium; bromide (3.4 g, 9.4mmol) in anhydrous THF (12 mL) was added n-BuLi (2.5 M, 3.8 mL) dropwiseat 0° C. under N₂. The mixture was stirred at 0° C. for 1 h. 311-3 (1.55g, 2.35 mmol) in THF (8 mL) was added to the mixture dropwise at 0° C.The solution was warmed and stirred at 25° C. for 12 h. The reaction wasquenched with a sat. NH₄Cl solution. The mixture was extracted with EA(3×50 mL). The combined organic phase was washed with brine, dried withanhydrous Na₂SO₄, filtered and concentrated in vacuum. The residue waspurified by column chromatography (10%-20% EtOAc in PE) to give 311-4(1.1 g, 71.05%) as a white solid.

311-4 (501 mg, 758.9 mol) was dissolved in 9-BBN (0.5 M, 15 mL) in oneportion at 25° C. under N₂. The mixture was heated at 80° C. inmicrowave for 30 mins. Sat. aq. NaHCO₃ (5 mL) and H₂O₂ (30%, 2.5 mL) wasadded at 0° C. The mixture was stirred at 25° C. for 2 h. The reactionwas quenched with sat. Na₂S₂O₃ at 0° C. The mixture was diluted with EAand water. The aqueous phase was back-extracted with EA. The combinedorganic phase was washed with brine, dried with anhydrous Na₂SO₄,filtered and concentrated in vacuum. The residue was purified by columnchromatography (10%-25% EtOAc in PE) to give 311-5 (395 mg, 76.9%) as awhite solid.

To a solution of 311-5 (360 mg, 531.8 μmol) in anhydrous DCM (4 mL) wasadded TEA (215 mg, 2.13 mmol) and MsCl (73 mg, 638.26 mol) in DCM (1 mL)dropwise at 0° C. The mixture was stirred at 25° C. for 2 h. Thereaction was quenched with ice water and extracted with CH₂Cl₂. Theorganic layer was washed with brine and dried over anhydrous MgSO₄. Thesolution was filtered and concentrated to 311-6 (395 mg, crude) as abrown solid, which was used in the next step without furtherpurification.

To a solution of 311-6 (380 mg, 504 μmol) in anhydrous DMF (4 mL) wasadded NaN₃ (98 mg, 1.51 mmol) at 25° C. The mixture was stirred at 70°C. for 3 h. The reaction was quenched with water and extracted with EA.The organic layer was washed with brine, dried over MgSO₄ and filtered.The filtrate was concentrated at low pressure. The residue was purifiedby column chromatography (10%-30% EtOAc in PE) to give 311-7 (295 mg,83.5%) as a white solid.

To a stirred solution of 311-7 (295 mg, 420.3 mol) in anhydrous CH₃CN (3mL) was added DMAP (102.7 mg, 840.6 mol), TEA (85.1 mg, 840.6 mol) andTPSCl (247.9 mg, 840.6 mol) at 25° C. The mixture was stirred at 25° C.for 3 h. NH₃.H₂O (10 mL, 28%) was added, and the mixture was stirred for1 h. The mixture was diluted with EA, and washed with brine, dried overanhydrous Na₂SO₄, filtered and concentrated in vacuum. The residue waspurified by column chromatography (1%-2% MeOH in DCM) to give 311-8 (260mg, 88.3%) as a white solid.

311-8 (240 mg, 342.4 mol) was treated with 80% HCOOH (10 mL) at 25° C.The mixture was stirred at 70° C. for 2 h. The reaction was cooled to25° C. and then concentrated under reduced pressure. The residue waspurified on a silica gel column (2%-6% MeOH in DCM) to give 311 (85 mg,79.1%) as a white solid. ESI-TOF-MS: m/z=314.9 [M+H]⁺, 629.1 [2M+H]⁺.

Example 189 Compound 312

A solution of 312-1 (0.68 g, 1.07 mmol) in AcOH (10 mL) and TFA (0.25mL) was stirred 1 h at RT. The mixture was evaporated, and the residuecoevaporated with MeCN and toluene. Purification on silica column withMeOH:CH₂Cl₂ solvent system (2-12% gradient) afforded 312-1 (0.32 g,82%).

A mixture of 312-1 (0.32 g, 0.9 mmol) in THF (9 mL) and LiBH₄ (94 mg,3.6 mmol) was stirred 2 d at RT. The reaction was quenched withAcOH:EtOH, and the mixture evaporated. Purification on silica columnwith MeOH:CH₂Cl₂ solvent system (4-15% gradient) afforded 312-2 (80 mg,30%).

A mixture of 312-2 (80 mg, 0.27 mmol) in pyridine (3 mL) and isobutyricanhydride (90 μL, 0.55 mmol) was stirred overnight at RT. The mixturewas evaporated, and the residue coevaporated with toluene. Purificationon silica column with EtOAc:hexanes solvent system (30-100% gradient)yielded 312-3 (72 mg, 61%) as a white solid.

To a solution of 312-3 (72 mg, 0.17 mmol) in MeCN (2 mL) were addedtriisopropylphenylsulfonyl chloride (102 mg, 0.34 mmol), DMAP (41 mg,0.34 mmol) and Et₃N (47 μL, 0.34 mmol). The mixture was stirred at RTfor 90 mins, and then ammonia was quickly bubbled (<1 min) through. Themixture was stirred for 10 mins. The mixture was diluted with CH₂Cl₂,washed with 0.1 N HCl, sat. aq. NaHCO₃, and brine, and dried withNa₂SO₄. Purification on silica column with MeOH:CH₂Cl₂ solvent system(4-12% gradient) afforded 312 (46 mg, 60%). MS: m/z=434.00 [M−1].

Example 190 Compound 313

To a solution of isobutiric acid (278 μL, 3 mmol) in THF (5 mL) wasadded CDI (486 mg, 3 mmol). After 1 h the solution of isobutiric acidimidazolide was added to a stirred solution of 106 (600 mg, 2 mmol),triethylamine (560 μL, 4 mmol) and DMAP (0.2 mmol) in DMF (5 mL). Thesolution was left overnight at RT. The reaction was partitioned betweenisopropyl acetate and sat. aq. ammonium chloride. The organic phase waswashed with water and concentrated under reduced pressure. 313 (500 mg,67%) was isolated by column chromatography (10 to 15% MeOH in DCM)followed by crystallization from isopropanol:hexane (1:2) as a whitesolid. MS: m/z 371 [M+H]⁺.

Example 191 Compound 314

To a stirred solution of 314-1 (2.16 g, 4.73 mmol) in ACN (20 mL) wereadded triethylamine (1.9 mL, 15 mmol), DMAP (60 mg, 0.5 mmol) andisobutyric anhydride (1.08 mL, 6.5 mmol). The mixture was stirred at RTfor 1 h, and then partitioned between isopropyl acetate and sat. aq.sodium bicarbonate solution. The organic phase was separated, washedwith water and concentrated. 314-2 (2.1 g, 84%) was isolated by columnchromatography using 25 to 50% EA in hexane as a white foam. MS: m/z 528[M+H]⁺.

314-2 (2.1 g, 3.98 mmol) was dissolved in ACN (15 mL) and the solutionwas cooled to 0° C. Triethylamine (1.1 mL, 8 mmol) and DMAP (537 mg, 4.4mmol) were added to the solution followed by addition oftriisopropylbenzenesulfonyl chloride (1.33 g, 4.4 mmol). The mixture waswarmed to RT and then stirred for 1 h. The reaction was quenched withammonium hydroxide (1 mL). The mixture was stirred for 2 h at RT,diluted with isopropyl acetate and filtered from ammonium salts. Thefiltrate was washed with water and aq. sodium bicarbonate and thenconcentrated under reduced pressure. 314-3 (2.1 g, ˜100%) was isolatedby column chromatography using 4-10% MeOH in CH₂Cl₂ as a yellowish foam.MS: m/z 527 [M+H]⁺.

314-3 (1.10 g, 2.09 mmol) was dissolved in THF (6 mL). The solution wascooled to 0° C. and treated with 1M TBAF solution in THF (2.1 mL, 2.1mmol). The reaction was allowed to proceed for 1 h, and then quenched bythe addition of a sat. aq. ammonium chloride solution. 314 (450 mg, 58%)was extracted with isopropyl acetate and isolated by columnchromatography in 5-15% MeOH in CH₂Cl₂ as an off-white foam, MS: m/z 371[M+H]⁺.

Example 192 Compound 315

315-1 (400 mg) was dissolved in NH₃/methanol (10 mL), and the mixturewas kept at ambient temperature over 2 d. The solvent was evaporated,and the residue purified by silica gel chromatography in gradient ofMeOH in CH₂Cl₂ from 3% to 20%. The mixture of products was separated byRP HPLC on Synergy 4 micron Hydro-RP column (Phenominex). A lineargradient of MeOH from 0 to 50% in 50 mM triethylammonium acetate buffer(pH 7.5) was used for elution. The corresponding fractions werecollected, concentrated and lyophilized (3×) to remove excess of buffer.The stereochemistry at the 1′-position of both isomers was proved by NOENMR-experiments. The compound with shorter retention time was 315. MS:m/z 319 [M+1]⁺, 637 [2M+1]⁺.

Example 193 Compound 316

316-1 (6.0 g, 14.77 mmol) was treated with NH₃ in MeOH (7.0 M, 150 mL)at RT. The mixture was stirred at 60° C. for 16 h. The mixture wasconcentrated under reduced pressure. The residue was purified by columnchromatography (5% MeOH in DCM) to give 316-2 (3.4 g, 90%) as a whitesolid.

To a stirred suspension of 316-2 (3.4 g, 13.1 mmol) in anhydrous THF (60mL) was added pyridine (15 mL), imidazole (1.8 g, 26.5 mol) and PPh₃(5.1 g, 19.5 mol). A solution of I₂ (4.3 g, 16.9 mol) in THF (20 mL) wasadded dropwise at 0° C. The mixture was warmed to RT and stirred for 16h. The reaction was quenched with sat. aq. Na₂S₂O₃ solution andextracted with EA (3×100 mL). The organic layer was dried over anhydrousNa₂SO₄, filtered and concentrated under reduced pressure. The residuewas purified by column chromatography (40% EA in PE) to afford 316-3(4.6 g, crude) as a white solid.

To a solution of 316-3 (4.6 g, crude) in THF (35 mL) was added DBU (37.8g, 247 mmol). The mixture was stirred at RT for 0.5 h. The mixture wasneutralized with acetic acid to pH=7 and extracted with EA (3×100 mL).The organic layer was washed with brine, dried over anhydrous Na₂SO₄ andfiltered. The filtrate was concentrated under reduced pressure. Theresidue was purified by column chromatography (50% EA in PE) to give316-4 (1.59 g, crude, 84% purity) as a white solid.

To an ice-cold solution of 316-4 (1.59 g, crude) in anhydrous MeCN (35mL) was added NEt₃.3HF (1.06 g, 6.56 mmol 1) and NIS (3.69 g, 16.40mmol) at 0° C. The mixture was stirred at 0° C. for 1 h. After thereaction was completed, the reaction was quenched with sat. aq. Na₂S₂O₃solution and sat. aq. NaHCO₃ solution and extracted with EA (3×100 mL).The organic layer was dried over anhydrous Na₂SO₄ and concentrated atlow pressure. The residue was purified by column chromatography (50% EAin PE) to give 316-5 (2.0 g, two isomers) as a white solid.

To a solution of 316-5 (2.0 g, 5.15 mmol, two isomers) in anhydrous DCM(30 mL) was added DMAP (1.57 g, 12.88 mmol) and BzCl (1.27 g, 9.01mmol), and the mixture was stirred at RT for 16 h. The reaction wasquenched with sat. aq. NH4Cl solution and extracted with DCM (3×60 mL).The organic layer was dried over anhydrous Na2SO4, filtered andconcentrated under reduced pressure. The residue was purified by columnchromatography (25% EA in PE) to give the crude product. The crude wasfurther purified by SFC separation (neutral conditions) to give 316-6(1.60 g, 63.1%) as a white solid.

To a solution of 316-6 (573 mg, 1.16 mmol) in dry DMF (30 mL) was addedNaOBz (1.68 g, 11.64 mmol) and 15-crown-5 (3.08 g, 13.97 mmol), and themixture was stirred at 90-110° C. for 24 h. The mixture was filtered andextracted with EA (3×20 mL). The organic layer was washed with brine,dried over anhydrous Na₂SO₄, filtered and concentrated at low pressure.The residue was purified by column chromatography (30% EA in PE) to give316-7 (492 mg, 87.20%) as a white solid.

316-7 (293 mg, 0.6 mmol) was treated with NH₃ in MeOH (30 mL, 7.0 M).The mixture was stirred at 60° C. for 16 h, and then concentrated underreduced pressure. The residue was purified by column chromatography (3%isopropanol in DCM) to give the crude product. The crude product waspurified by prep-HPLC (FA condition) to give 316 (108 mg, 53.41%) as awhite solid. ESI-TOF-MS: m/z=279.1 [M+H]⁺.

Example 194 Compound 317

To a solution of 316-7 (492 mg, 1.01 mmol) in anhydrous CH₃CN (8 mL)were added DMAP (308 mg, 2.53 mmol), Et₃N (255 mg, 2.53 mmol) and2,4,6-triisopropylbenzene-1-sulfonyl chloride (765 mg, 2.53 mmol) at RT.The mixture was stirred at RT overnight. A solution of NH₃ in THF (4 mL,7.0 M) was added, and the mixture was stirred for 30 mins. The solventwas removed under reduced pressure. The residue was diluted with EA. Thesolution was washed with 0.5% AcOH aq. solution and brine. The organiclayer was dried over anhydrous Na₂SO₄, filtered and concentrated underreduced pressure. The residue was purified by column chromatography (2%MeOH in DCM) and further purified by prep-TLC (10% MeOH in DCM) to give317-1 (370 mg, 65.6%) as a white solid.

317-1 (370 mg, 0.76 mmol) was treated with NH₃ in MeOH (40 mL, 7.0 M).The mixture was stirred at 60° C. for 16 h. The mixture was concentratedunder reduced pressure. The residue was purified by columnchromatography (8% isopropanol in DCM) to give the crude product. Thecrude product was purified by prep-HPLC (FA condition) to give 317 (65.6mg, 30.2%) as a white solid. ESI-TOF-MS: m/z=278.1 [M+H]⁺, 555.2[2M+H]⁺.

Example 195 Compound 318

364-1 (50 mg, 0.081 mmol) was dissolved in anhydrous CH₃CN (1.0 mL), and4N HCl in dioxane (81 μL, 0.32 mmol) was added at 0 to 5° C. The mixturewas stirred at RT for 1 h. The solvents were evaporated at RT andco-evaporated with toluene (3×). The residue was purified on silica gelcolumn using 15-30% EA:DCM to give 364 (25.6 mg, 92%) as a white solidafter evaporation. ESI-LCMS: m/z=346.05 [M+H]⁺

Example 196 Compound 319

To a stirred solution of 318-1 (300 mg, 0.49 mmol) in anhydrous pyridine(3.0 mL) were added TBDPSCl (0.27 mL, 0.97 mmol) and DMAP (119 mg, 0.97mmol) at 0 OC (ice/water bath). The solution was stirred at RT for 16 h.The mixture was cooled to 0 to 5° C. The reaction was quenched with EtOH(0.3 mL), diluted with EA (100 mL). Water (50 mL) was added to themixture. The solution was washed with sat. aq. NaHCO₃ and brine, anddried with MgSO₄. The residue was purified on silica with EA:hexanes(10-100% gradient) to give 319-1 (386 mg, 93%) as an off white foam.

To a stirred solution of 319-1 (300 mg, 0.49 mmol) in anhydrous CH₃CN(4.0 mL) were added 319-2 (331.0 mg, 0.94 mmol, was prepared accordingto procedure described in Katritzky et al., Synthesis (2004)2004(16):2645-2652), DIPEA (0.17 mL, 0.94 mmol) and DMAP (115 mg, 0.94mmol). The solution was stirred at 70° C. for 16 h. The mixture wascooled to 0 to 5° C., diluted with EA (100 mL) and then water (50 mL)was added. The solution was washed with sat. aq. NaHCO₃ and brine, anddried with MgSO₄. The residue was purified on silica with EA:hexanes(10-100% gradient) to give 319-3 (174 mg, 70%) as a yellow foam.

To a solution of 319-3 (166 mg, 0.153 mmol) in THF (2 mL), was added3TEA.HF (98 μL, 0.61 mmol) and TEA (66 μl, 0.46 mmol) at ice bathtemperature. The mixture was stirred for 18 h at RT. The mixture wasdiluted with EA and washed with water and brine. The organic layer wasdried and concentrated to give the crude product, which was purified bysilica gel column chromatography EA:hexanes (20-100% gradient) to give319-4 (106 mg, 81.5%) as a white foam.

To a solution of triethylammonium bis (POC) phosphate (0.36 mmol,prepared from 118 mg of bis (POC) phosphate and 0.5 mL of TEA) in THF (3mL) was added 319-4 (102 mg, 0.12 mmol) followed by3-nitro-1,2,4-triazole (48 mg, 0.42 mmol), diisopropylethyl amine (0.11mL, 0.6 mmol) and BOP-Cl (107 mg, 0.42 mmol) at 0 to 5° C. (ice waterbath). The mixture was stirred at 2 h, diluted with EtOAc and washedwith water and brine. The organic layer was separated, dried overanhydrous Na₂SO₄ and filtered. The filtrate was concentrated in vacuumto give a white solid, which was purified on silica gel column(EA:hexanes 5 to 60%) to give 319-5 as a light yellow foam (106 mg,78%).

319-5 (102 mg, 0.088 mmol) was dissolved in anhydrous CH₃CN (0.7 mL),and 4N HCl in dioxane (55 μL, 0.22 mmol) was added at 0 to 5° C. Themixture was stirred at RT for 1 h, and then anhydrous EtOH (100 μL) wasadded. The solvents were evaporated at RT and co-evaporated with toluene(3×). The product was purified on silica gel column (EA:hexanes 15 to100%) to give 319-6 as a white foam (60.3 mg, 77%)

319-6 (40 mg, 0.044 mmol) was dissolved in anhydrous EtOH (1.3 mL),degassed (3×), flushed H₂, and then 10% Pd/C (6 mg) and 4N HCl indioxane (22 μL, 0.089 mmol) were added. The mixture was stirred under H₂atmosphere at RT for 2 h. The mixture was filtered through celite, andthe celite was washed with anhydrous EtOH (1.5 mL). The solvents wereevaporated, and triturated with anhydrous diethyl ether (3×1.5 mL). Theether layer was decanted, and the solid obtained was dried in highvacuum to give 319 (26.8 mg, 79.7%, hydrochloride salt) as a whitesolid. ESI-LCMS: m/z=757.2 [M+H]⁺.

Example 197 Compound 320

320 was prepared according to the procedure described for 319-5 startingfrom 316 (36.5 mg, 0.13 mmol) and a solution of triethylammonium bis(POC) phosphate (0.26 mmol, prepared from bis (POC) phosphate (85 mg)and TEA (0.5 mL) in THF (1 mL)). ESI-LCMS: m/z=589.0 [M−H]⁻.

Example 184 Compounds of Formula (I)

Some compounds of Formula (I) are commercially available. For somecompounds, the foregoing syntheses are exemplary and can be used as astarting point to prepare additional compounds of Formula (I). Examplesof additional compounds of Formula (I) are shown below. These compoundscan be prepared in various ways, including those synthetic schemes shownand described herein. Those skilled in the art will be able to recognizemodifications of the disclosed syntheses and to devise routes based onthe disclosures herein; all such modifications and alternate routes arewithin the scope of the claims.

Example 185 MERS Assay

Cells and Virus:

Human lung carcinoma cells (A-549) were used for the primary antiviralassays and were obtained from American Type Culture Collection (ATCC,Rockville, Md., USA). The cells were routinely passed in minimalessential medium (MEM with 0.15% NaCHO3, Hyclone Laboratories, Logan,Utah, USA) supplemented with 10% fetal bovine serum. When evaluatingcompounds for efficacy, the serum was reduced to a final concentrationof 2% and the medium contained gentamicin (Sigma-Aldrich, St. Louis,Mo.) at 50 μg/mL. Since the MERS-Co virus did not produce detectablevirus cytopathic effects, virus replication in A549 cells was detectedby titering virus supernatant fluids from infected, compound-treatedA549 cells in Vero 76 cells. Vero 76 cells were obtained from ATCC andwere routinely passed in MEM with 0.15% NaCHO3 supplemented with 5%fetal bovine serum. When evaluating compounds, the serum was reduced toa final concentration of 2% and supplemented with 50 μg/mL ofgentamicin.

The Middle Eastern coronavirus strain EMC (MERS-CoV) was an originalisolate from humans that was amplified in cell culture by Ron Fouchier(Erasmus Medical Center, Rotterdam, the Netherlands) and was obtainedfrom the Centers for Disease Control (Atlanta, Ga.).

Controls:

Infergen® (interferon alfacon-1, a recombinant non-naturally occurringtype-I interferon (Blatt, L., et al., J. Interferon Cytokine Res. (1996)16(7):489-499 and Alberti, A., BioDrugs (1999) 12(5):343-357) was usedas the positive control drug in all antiviral assays. Infergen=0.03ng/mL.

Antiviral Assay:

Virus was diluted in MEM to a multiplicity of infection=0.001 and eachcompound was diluted in MEM+2% FBS using a half-log 8 dilution series.Compound was added first to 96 well plates of confluent A549 cellsfollowed within 5 mins by virus. Each test compound dilution wasevaluated for inhibition in triplicate. After plating, the plates wereincubated at 37° C. for 4 d. The plates were then frozen at −80° C.

Virus Yield Reduction Assay:

Infectious virus yields from each well from the antiviral assay weredetermined. Each plate from an antiviral assays was thawed. Sampleswells at each compound concentration tested were pooled and titered forinfectious virus by CPE assay in Vero 76 cells. The wells were scoredfor CPE and virus titers calculated. A 90% reduction in virus yield wasthen calculated by regression analysis. This represented a one log₁₀inhibition in titer when compared to untreated virus controls.

Compounds of Formula (I) are active against MERS. The antiviral activityof exemplary compounds is shown in Table 3, where ‘A’ indicates anEC₉₀<10 μM, ‘B’ indicates an EC₉₀≧10 μM and <50 μM, and ‘C’ indicates anEC₉₀≧50 μM and <100 μM.

TABLE 3 Compound EC₉₀ 25 B 27 B 36 A 57 A 265 B 266 A 267 B

Example 186 VEEV Assay

96-well plates of HeLa-Ohio cells were prepared and incubated overnight.The plates were seeded at 4×10⁴ cells per well, which yielded 90-100%confluent monolayers in each well after overnight incubation. The testcompounds in DMSO were started at a concentration of 100 μM. 8-foldserial dilutions in MEM medium with 0.1% DMSO, 0% FBS, and 50 μg/mLgentamicin with the test compound concentrations were prepared. To 5test wells on the 96-well plate was added 100 μL of each concentrationand the plate was incubated at 37° C.+5% CO₂ for 2 h or 18 h. 3 wells ofeach dilution with the TC-83 strain Venezuelan equine encephalitis virus(ATCC, stock titer: 10^(6.8) CCID₅₀/mL) prepared in the medium asdescribed above were added. 2 wells (uninfected toxicity controls) wereadded MEM with no virus. 6 wells were infected with untreated viruscontrols. To 6 wells were added media only as cell controls. A blind,known active compound was tested in parallel as a positive control. Theplate was incubated at 37° C.+5% CO₂ for 3 d. The plate was readmicroscopically for visual CPE and a Neutral red dye plate was also readusing BIO-TEK Instruments INC. EL800. For virus yield reduction assays,the supernatant fluid was collected from each concentration. Thetemperature was held at −80° and each compound was tested in triplicate.The CC₅₀ was determined by regression analysis using the CPE of toxicitycontrol wells compared with cell controls. The virus titers were testedin triplicate using a standard endpoint dilution CCID₅₀ assay and titercalculations were determined using the Reed-Muench (1948) equation. Theconcentration of compound required to reduce virus yield by 1 log₁₀(90%) using regression analysis was calculated (EC₉₀ value). Theconcentration of compound required to reduce virus yield by 50% usingregression analysis were calculated (EC₅₀ value).

Compounds of Formula (I) are active against VEEV. Compounds 9, 25, 55and 265 all had an EC₅₀ value <10 μM with a 2 h pre-incubation.Compounds 9, 55 and 265 all had an EC₅₀ value <10 μM with an 18 hpre-incubation.

Example 187 Rift Valley Fever Assay

Compounds of Formula (I) were tested for activity against Rift ValleyFever virus using methods known to those skilled in the art (e.g.,described in Panchal et al., Antiviral Res. (2012) 93(1):23-29).

Example 188 Chikungunya Assay

Compounds of Formula (I) were tested for activity against Chikungunyavirus using methods known to those skilled in the art. Compounds ofFormula (I) are active against Chikungunya virus. Compounds 9, 25, 55and 265 all had an EC₅₀ value <10 μM with a 2 h pre-incubation.

Example 189 SARS Assay

Compounds of Formula (I) were tested for activity against the SARS virususing methods known to those skilled in the art, for example, SARSpolymerase assay. Compounds of Formula (I) are active against the SARSvirus. Compounds 19, 34, 101, 103, 123, 162, 203 and 246 all had an IC₅₀value <10 μM.

Example 190 Coronavirus Assay

The human β-coronavirus strain OC43 and the human α-coronavirus strain229E were purchased from ATCC (Manassas, Va.; item numbers VR-1558 andVR-740, respectively). 24 hours prior to dosing, HeLa human cervixepithelial cells (ATCC, CCL-2) or MRC-5 human lung fibroblast (ATCC,CCL-171) were plated in 96 well plates at a density of 1.5×10⁵/mL inDMEM medium supplemented with 10% fetal bovine serum, 1% HEPES buffer,1% Penicillin/Streptomycin and 1% non-essential amino acids (allMediatech, Manassas, Va.). At the day of infection, serially dilutedcompounds were added to cells and incubated for 4 h. After the end ofthe 4 h pre-incubation period, cells were infected with eithercoronavirus strain OC43 or 229E. The virus inoculum was selected tocause 80-90% cytopathic effect. Infected cells were incubated for 5 daysat 37° C., 5% CO₂. To develop the assay, 100 μL media was replaced with100 μL CellTiter-Glo®reagent (Promega, Madison, Wis.), and incubated for10 mins at RT. Luminescence was measured on a Victor X3 multi-labelplate reader. Potential compound cytotoxicity of was determined usinguninfected parallel cultures.

Compounds of Formula (I) are active against coronavirus virus. Compounds14, 22, 55, 57, 83, 84, 212a, 212b, 225 and 234 inhibited coronavirusvirus at ≧50% (≧50% inhibition) at one or more of the followingconcentrations: 75 μM, 60 μM, 10 μM and 2 μM. Compounds 16, 55, 57, 83,179, 212a and 212b all had an EC₅₀ value <10 μM.

Although the foregoing has been described in some detail by way ofillustrations and examples for purposes of clarity and understanding, itwill be understood by those of skill in the art that numerous andvarious modifications can be made without departing from the spirit ofthe present disclosure. Therefore, it should be clearly understood thatthe forms disclosed herein are illustrative only and are not intended tolimit the scope of the present disclosure, but rather to also cover allmodification and alternatives coming with the true scope and spirit ofthe invention.

What is claimed is:
 1. A method for ameliorating or treating a viralinfection comprising contacting a cell infected with a virus with aneffective amount of a compound of Formula (I), or a pharmaceuticallyacceptable salt thereof, wherein the compound of Formula (I) has thestructure:

wherein: B^(1A) is selected from the group consisting of:

wherein R^(G2) is an unsubstituted C₁₋₆ alkyl; R^(3A) is halo or OH;R^(4A) is OH or halo; R^(a1) and R^(2a) are independently hydrogen ordeuterium; R^(A) is hydrogen or deuterium; R^(1A) is selected from thegroup consisting of hydrogen

R^(2A) is hydrogen, halo, —(CH₂)₁₋₆halogen, or —(CH₂)₁₋₆N₃; R^(5A) isselected from the group consisting of hydrogen, an unsubstituted C₁₋₆alkyl, an unsubstituted C₂₋₆ alkenyl and an unsubstituted C₂₋₆ alkynyl;R^(6A) and R^(7A) are independently selected from the group consistingof absent, hydrogen and

R^(6A) is

and R^(7A) is absent or hydrogen; R^(8A) is an optionally substitutedphenyl or an optionally substituted naphtyl; R^(9A) is an optionallysubstituted N-linked α-amino acid or an optionally substituted N-linkedα-amino acid ester derivative; R^(10A) and R^(11A) are independently anoptionally substituted N-linked α-amino acid or an optionallysubstituted N-linked α-amino acid ester derivative; R^(12A) and R^(13A)are independently absent or hydrogen; R^(14A) is O⁻ or OH; R^(22A) andR^(23A) are each hydrogen; R^(24A) selected from the group consisting ofhydrogen, an optionally substituted C₁₋₂₄ alkyl and substituted—O—C₁₋₂₄alkyl; m is 0 or 1; s is 0, 1, 2 or 3; and Z^(1A), Z^(2A),Z^(3A) and Z^(4A) are O; wherein the virus is selected from the groupconsisting of MERS-CoV, SARS-CoV, Venezuelan equine encephalitis virus,Chikungunya virus and coronavirus; and when a group is substituted, thegroup is substituted with one or more substituents selected from thegroup consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl,aryl, heteroaryl, heterocyclyl, aryl(alkyl), heteroaryl(alkyl),(heterocycyl)alkyl, hydroxy, alkoxy, acyl, cyano, halogen, thiocarbonyl,O-carbamyl, N-carbamyl, O-thiocarbamyl, N-thiocarbamyl, C-amido,N-amido, S-sulfonamido, N-sulfonamido, C-carboxy, O-carboxy, isocyanato,thiocyanato, isothiocyanato, nitro, azido, silyl, sulfenyl, sulfinyl,sulfonyl, haloalkyl, haloalkoxy, trihalomethanesulfonyl,trihalomethanesulfonamido, an amino, a mono-substituted amino group anda di-substituted amino group; and wherein an —N-linked α-amino acidester derivate refers to an α-amino acid in which a main-chaincarboxylic acid group has been converted to an ester group.
 2. Themethod of claim 1, wherein the virus is a coronavirus.
 3. The method ofclaim 1, wherein the virus is MERS-CoV or SARS-CoV.
 4. The method ofclaim 1, wherein the virus is a Venezuelan equine encephalitis virus orChikungunya virus.
 5. The method of claim 1, wherein R^(2A) is hydrogen.6. The method of claim 1, wherein R^(2A) is halo.
 7. The method of claim6, wherein the halo is fluoro.
 8. The method of claim 1, wherein R^(2A)is —(CH₂)₁₋₆ halogen or —(CH₂)₁₋₆N₃.
 9. The method of claim 8, whereinR^(2A) is —(CH₂)₁₋₆F.
 10. The method of claim 1, wherein R^(4A) is OH.11. The method of claim 1, wherein R^(4A) is halo.
 12. The method ofclaim 11, wherein the halo is F or Cl.
 13. The method of claim 1,wherein R^(5A) is hydrogen.
 14. The method of claim 1, wherein R^(5A) isan unsubstituted C₁₋₆ alkyl.
 15. The method of claim 1, wherein R^(1A)is hydrogen.
 16. The method of claim 1, wherein R^(1A) is


17. The method of claim 16, wherein R^(6A) is absent or hydrogen; andR^(7A) is absent or hydrogen.
 18. The method of claim 16, wherein R^(6A)and R^(7A) are independently

wherein s is 0; and R^(24A) is an unsubstituted C₁₋₄ alkyl.
 19. Themethod of claim 1, wherein R^(1A) is


20. The method of claim 19, wherein R^(8A) is an optionally substituted;and R^(9A) is an optionally substituted N-linked α-amino acid selectedfrom the group consisting of N-linked alanine, N-linked glycine,N-linked valine, and N-lined leucine, or an optionally substitutedN-linked α-amino acid ester derivative, wherein the N-linked α-aminoacid is selected from the group consisting of N-linked alanine, N-linkedglycine, N-linked valine and N-linked leucine, and the ester is selectedfrom the group consisting of alkyl ester, cycloalkyl ester, andoptionally substituted phenyl ester and an optionally substituted benzylester.
 21. The method of claim 1, wherein R^(1A) is


22. The method of claim 21, wherein R^(10A) and R^(11A) areindependently an optionally substituted N-linked α-amino acid selectedfrom the group consisting of N-linked alanine, N-linked glycine,N-linked valine and N-linked leucine, or an optionally substitutedN-linked amino α-acid ester derivative, wherein the N-linked α-aminoacid is selected from the group consisting of N-linked alanine, N-linkedglycine, N-linked valine and N-linked leucine, and the ester is selectedfrom the group consisting of alkyl ester, cycloalkyl ester, andoptionally substituted phenyl ester and an optionally substituted benzylester.
 23. The method of claim 1, wherein R^(3A) is halo.
 24. The methodof claim 23, wherein the halo is fluoro.
 25. The method of claim 1,wherein R^(3A) is OH.
 26. The method of claim 1, wherein R^(A) ishydrogen.
 27. The method of claim 1, wherein R^(a1) and R^(a2) are bothhydrogen.
 28. The method of claim 1, wherein B^(1A) is


29. The method of claim 1, wherein B^(1A) is


30. The method of claim 1, wherein the compound of Formula (I) isselected from the group consisting of:

or a pharmaceutically acceptable salt of any of the foregoing.
 31. Themethod of claim 1, wherein the compound is selected from the groupconsisting of:

or a pharmaceutically acceptable salt of any of the foregoing.
 32. Themethod of claim 1, wherein the compound is selected from the groupconsisting of:

or a pharmaceutically acceptable salt of any of the foregoing.
 33. Themethod of claim 1, wherein the compound is selected from the groupconsisting of:

or a pharmaceutically acceptable salt of any of the foregoing.
 34. Themethod of claim 1, wherein R^(5A) is an unsubstituted C₂₋₆ alkynyl. 35.The method of claim 34, wherein R^(5A) is an ethynyl.
 36. The method ofclaim 14, wherein R^(5A) is methyl.
 37. The method of claim 16, whereinR^(6A) and R^(7A) are independently

wherein s is 0; and R^(24A) is an unsubstituted —O—C₁₋₄ alkyl.
 38. Themethod of claim 16, wherein R^(6A) is

m is 0; and R^(7A), R^(12A) and R^(13A) are independently absent orhydrogen.
 39. The method of claim 16, wherein R^(6A) is

m is 1; R^(7A), R^(12A) and R^(13A) are independently absent orhydrogen; and R^(14A) is O⁻ or OH.
 40. The method of claim 1, whereinR^(2A) is fluoromethyl.
 41. The method of claim 1, wherein R^(2A) isazidomethyl.
 42. The method of claim 20, wherein R^(8A) is an optionallysubstituted phenyl; and R^(9A) is selected from the group consisting ofN-linked alanine, N-linked alanine isopropyl ester, N-linked alaninecyclohexyl ester and N-linked alanine neopentyl ester.
 43. The method ofclaim 30, wherein B^(1A) is


44. The method of claim 30, wherein B^(1A) is


45. The method of claim 30, wherein B^(1A) is


46. A method for ameliorating or treating a viral infection comprisingcontacting a cell infected with a virus with an effective amount of acompound of Formula (I), or a pharmaceutically acceptable salt thereof,wherein the compound of Formula (I) has the structure:

wherein: B^(1A) is selected from the group consisting of:

wherein R^(G2) is an unsubstituted C₁₋₆ alkyl; R^(3A) is O; R^(4A) ishalo; R^(1B) is an —O-unsubstituted C₁₋₆ alkyl; R^(a1) and R^(a2) areindependently hydrogen or deuterium; R^(A) is hydrogen or deuterium;R^(2A) is halo; R^(5A) is an unsubstituted C₁₋₆ alkyl; Z^(1B) is O or S;wherein the virus selected from the group consisting of MERS-CoV,SARS-CoV, Venezuelan equine encephalitis virus, Chikungunya virus and acoronavirus.
 47. The method of claim 46, wherein the compound is

is or a pharmaceutically acceptable salt thereof.
 48. The method ofclaim 46, wherein the compound is selected from the group consisting of:

or a pharmaceutically acceptable salt of any of the foregoing.